Battery Issue
Junior Member
Joined: Feb 2020
Posts: 1
Likes: 0
From: Lake Tahoe
Same problem on 2000 XKR
I'm hoping someone has some experience to help me figure out this recurring problem because the local "expert" dealership mechanics can't figure it out or, more likely, are not interested in figuring it out. So, I bring my car for service and when I pick it up it says "Low Battery Start your Car." I go inside and ask what they did to kill my battery and they said they probably just had the door open while they were servicing it too long etc and so on. OK fine, that was about a year ago and it was the original battery so (Car is 2016) so I don't think much of it. Drive the car a few times over through the year, no issues, starts right up. Let it sit for a little longer than normal earlier this year and the battery was dead. Jumped it and took it to the dealership for a new one. Dealer says they have to check everything (So they can charge me for it) and reports back that everything was good, alternator is fine and system seems good and I just need a new battery to the tune of $700. Play expensive games win expensive prizes. Drive the car home park it in the garage. Now I add the insurance company plug in to get a discount on my mileage. Go out 2 (Two) days later and its dead. Completely dead not sort of dead. Odd, because my 15 year old car with mystery age battery can handle the billionth of an amp draw from the insurance dongle, but the Jag can't? Call the dealership back. "We're so sorry must have been a defective battery." Bring it back to the dealership. They swap batteries allegedly. I bring the car home park it in the garage and one week later...dead again. Call the dealership, bring it back. After a week they tell me the insurance dongle is not letting the car "go to sleep" and must be draining the battery. Whatever, take the dongle out and bring it home. All is good no more dongle. 3 days later...dead. Back to the dealership, seriously, and after another week they tell me everything checks out ok and they have no idea whats wrong and the car starts just fine. So what can I do? Nothing but pick it up. Drive it home. 3 days later and it works! I take it to DMV to get it inspected no problems. Go home park it and 4 days later...dead again. I'm bringing it back this week.
Does anyone have any clue why batteries would keep getting shot like this. They claim my alternator is good and they have checked it 3 times now and I'm sure they'd be happy to charge me for a new one since the car is now out of warranty. I read somewhere that there are 2 batteries in the 2016s, one for starts and the main one. Is that true? But when I say the car is dead, its dead. Not even the LED dome lights come on. Plus it takes a long time charging it off my truck to even get it to try to start. Is there some relay that gets smoked after too many low voltage events or something? The dealership seems to have no interest in fixing this but if I bring it to another one I just don't want to go through the same disaster. Assuming they actually changed my original battery, I cannot believe I got 3 bad batteries in a row. There is nothing plugged into the car to draw power. For the first 4 years we had the car, I could let it sit for two months or more with no battery tender (I know not the best idea) and it would start with no issues. Since the original battery died, it will not last for more than a few days before it is dead again. Any thoughts or suggestions would be greatly appreciated.
Does anyone have any clue why batteries would keep getting shot like this. They claim my alternator is good and they have checked it 3 times now and I'm sure they'd be happy to charge me for a new one since the car is now out of warranty. I read somewhere that there are 2 batteries in the 2016s, one for starts and the main one. Is that true? But when I say the car is dead, its dead. Not even the LED dome lights come on. Plus it takes a long time charging it off my truck to even get it to try to start. Is there some relay that gets smoked after too many low voltage events or something? The dealership seems to have no interest in fixing this but if I bring it to another one I just don't want to go through the same disaster. Assuming they actually changed my original battery, I cannot believe I got 3 bad batteries in a row. There is nothing plugged into the car to draw power. For the first 4 years we had the car, I could let it sit for two months or more with no battery tender (I know not the best idea) and it would start with no issues. Since the original battery died, it will not last for more than a few days before it is dead again. Any thoughts or suggestions would be greatly appreciated.
Veteran Member
Joined: Feb 2011
Posts: 3,918
Likes: 2,522
From: Victoria, Canada
Well....the second, smaller battery (stop/start related) was never in the engine compartment; always found in the foor cavity if the trunk/boot, to the right.
Junior Member
Joined: Nov 2015
Posts: 6
Likes: 2
From: Indiana
Can't answer your specific question, but am amazed at people buying batteries at the dealer when you can get a four year guaranteed replacement battery at Walmart for $169. Since your car does sit a trickle charger may solve the problem. Also many insurance companies have gone away from the plug in module and are now using smart phone apps. The plug in can be a problem. As a long time insurance agent I never recommend them, because of that and I don't want them to know my driving habits. With a Jaguar it's tough to obey the speed limit 
Junior Member
Joined: Jul 2015
Posts: 3
Likes: 0
From: Nevada
Battery - weird "twist"
I haven't read all the posts (ads were getting to me), so hopefully, I am bringing something new to the thread.
I'm not the best at dramatizing my experience (below), but your description sounds all too familiar to what my mechanic and I fixed by... tightening both ends of the ground cable (i.e. battery and where the cable attaches to the frame). I suggest removing the nut connecting the cable to the frame, make a couple of gouges on the metal of the cable and the car connection point, and wrench down on it when reattaching.
I cannot stress enough the value in the ground connections. My experience sounds very similar to yours, including my car going into "stealth" mode while driving at night. Stealth mode, in my words, is when the car shuts down non-critical electrical components in order to provide enough power for critical systems. In my case, the car would turn off the entire dash (including illumination of the gauges at night) so the engine, headlights, and signal lights would function.
I did just as you did over a year. I had everything checked by the dealer (Reno, NV, then Sacramento, CA). Replaced the battery ($$$). I replaced the ground cable thinking the in-line fuse had lost tolerance. I need to give a shout out to British Car Service in Sacramento. They are the ones who took the time to listen to me, then they pin tested the electrical current all through the car, including placing the key fobs in a safe that would not allow the car to receive signal (to rule out the "going to sleep" issue, which is a real thing in my opinion - always lock the car when not in it!) What British Car Service determined was although the ground connection to the metal frame was indeed tight, it was not tight enough to "bite" through the outer layers of the metal to allow for enough current to keep up with what all the electrical systems needed. There was no corrosion in the connections and there was a connection, the connection just didn't have enough...bandwidth(?)... for everything to function, which ultimately created battery drain, even while the car was sleeping - because the car was ultimately smart enough to know something wasn't right and would randomly wake up to perform some sort of self-check and keep doing this enough to drain the battery (prompt the warning message on the dash). I saw this a few times as I was working in the garage. I would be walking by the car and happen to see the center console screen light up for a minute or two while locked then go back to sleep. I would then open up the car and there was the battery warning message.
British Car Service scored the ground connection point on the frame/metal as well as on the battery terminal and added a dab of grease. Poof! Problem solved with no issues for five years (knock on wood).
Anyway, it's a labor of love with these things, especially with all the electrical components. The kitty has definitely been my most high-maintenance toy, and I also have a boat.
I'm not the best at dramatizing my experience (below), but your description sounds all too familiar to what my mechanic and I fixed by... tightening both ends of the ground cable (i.e. battery and where the cable attaches to the frame). I suggest removing the nut connecting the cable to the frame, make a couple of gouges on the metal of the cable and the car connection point, and wrench down on it when reattaching.
I cannot stress enough the value in the ground connections. My experience sounds very similar to yours, including my car going into "stealth" mode while driving at night. Stealth mode, in my words, is when the car shuts down non-critical electrical components in order to provide enough power for critical systems. In my case, the car would turn off the entire dash (including illumination of the gauges at night) so the engine, headlights, and signal lights would function.
I did just as you did over a year. I had everything checked by the dealer (Reno, NV, then Sacramento, CA). Replaced the battery ($$$). I replaced the ground cable thinking the in-line fuse had lost tolerance. I need to give a shout out to British Car Service in Sacramento. They are the ones who took the time to listen to me, then they pin tested the electrical current all through the car, including placing the key fobs in a safe that would not allow the car to receive signal (to rule out the "going to sleep" issue, which is a real thing in my opinion - always lock the car when not in it!) What British Car Service determined was although the ground connection to the metal frame was indeed tight, it was not tight enough to "bite" through the outer layers of the metal to allow for enough current to keep up with what all the electrical systems needed. There was no corrosion in the connections and there was a connection, the connection just didn't have enough...bandwidth(?)... for everything to function, which ultimately created battery drain, even while the car was sleeping - because the car was ultimately smart enough to know something wasn't right and would randomly wake up to perform some sort of self-check and keep doing this enough to drain the battery (prompt the warning message on the dash). I saw this a few times as I was working in the garage. I would be walking by the car and happen to see the center console screen light up for a minute or two while locked then go back to sleep. I would then open up the car and there was the battery warning message.
British Car Service scored the ground connection point on the frame/metal as well as on the battery terminal and added a dab of grease. Poof! Problem solved with no issues for five years (knock on wood).
Anyway, it's a labor of love with these things, especially with all the electrical components. The kitty has definitely been my most high-maintenance toy, and I also have a boat.
Junior Member
Joined: Aug 2018
Posts: 12
Likes: 6
From: Pittsburgh PA
Couple of points, the alternator should absolutely be capable of recharging the battery at normal driving speeds in about 15-20 minutes, if it doesn't the alternator is either defective, or there is something else drawing major amounts of current in the system, beyond the normal system draw, to be preventing a decent charge. The whole point of having an alternator IS TO CHARGE THE BATTERY. I don't care if you fully discharge a lead acid wet cell or AGM battery with a slow drain, if it's a week old, it should have no problems accepting a charge and be fine. Battery damage occurs when you draw so much power from the battery from a high current drain that you actually melt or distort the plates. drawing 3 or 5 amps for a couple hours/days is not going to overheat anything. If that hurts the battery it was garbage to begin with, and likely would have failed under vibration anyway. About the only way you can hurt one at low current drain, is if you manage to drain it and then it freezes because the ambient temp is low... that will distort and break stuff.
I have a 15 XF 5.0SC, and I've not had a problem with the battery yet, but I did have an instance where the car would not shut off... (that was a fun 2 hours) i pulled every relay under the hood and it wouldn't die... so I finally pulled the battery then it shut off. Then I couldn't get it to come back to life. So I left it connected for a day or two and came back out to try it, and it started up fine. Only problem is my wipers don't work now. The washer fluid will pump out, but the wipers will not move no matter what I do.
It's been a dry annoying and busy summer so I've yet to take it to the steel -er- ship to see what that's going to cost to fix it. Going to find out soon.
I have a 15 XF 5.0SC, and I've not had a problem with the battery yet, but I did have an instance where the car would not shut off... (that was a fun 2 hours) i pulled every relay under the hood and it wouldn't die... so I finally pulled the battery then it shut off. Then I couldn't get it to come back to life. So I left it connected for a day or two and came back out to try it, and it started up fine. Only problem is my wipers don't work now. The washer fluid will pump out, but the wipers will not move no matter what I do.
It's been a dry annoying and busy summer so I've yet to take it to the steel -er- ship to see what that's going to cost to fix it. Going to find out soon.
Junior Member
Joined: Jun 2019
Posts: 5
Likes: 0
From: Newton, MA
I had this problem too with my 2008 XK, and the two Auto Shops I took it to, both Jaguar specialists, said they routinely saw this electrical system problem with models 2005 - 2009, and often couldn't locate the exact cause. Because I also experienced the car's info system going down sometimes, I figured out it had to do with the Car's information/audio system. They are all interconnected and, as far as I know, you can't just replace one component. Anyway, through trial and error, I figured out that even when the car was off the CD disc player kept trying to load a different CD and thus drained the battery and affected the other info systems. So, now, I only load one CD into the player and indeed never leave a CD in the player even when the car is off. I haven't had any battery problem now for a year-and-a half, tho occasionally my info screen still won't go to Home.
Junior Member
Joined: Jun 2019
Posts: 1
Likes: 0
Didn't give that a thought
Just read an article about a stumper of a battery draw situation. Turned out that the owner left their car phone charger plugged in while not using the car. So, the draw would not let the car systems "go to sleep" and drew down the battery.
Just wondering if you have a similar item plugged into a power port when you are not in the car.
Just wondering if you have a similar item plugged into a power port when you are not in the car.
I'm hoping someone has some experience to help me figure out this recurring problem because the local "expert" dealership mechanics can't figure it out or, more likely, are not interested in figuring it out. So, I bring my car for service and when I pick it up it says "Low Battery Start your Car." I go inside and ask what they did to kill my battery and they said they probably just had the door open while they were servicing it too long etc and so on. OK fine, that was about a year ago and it was the original battery so (Car is 2016) so I don't think much of it. Drive the car a few times over through the year, no issues, starts right up. Let it sit for a little longer than normal earlier this year and the battery was dead. Jumped it and took it to the dealership for a new one. Dealer says they have to check everything (So they can charge me for it) and reports back that everything was good, alternator is fine and system seems good and I just need a new battery to the tune of $700. Play expensive games win expensive prizes. Drive the car home park it in the garage. Now I add the insurance company plug in to get a discount on my mileage. Go out 2 (Two) days later and its dead. Completely dead not sort of dead. Odd, because my 15 year old car with mystery age battery can handle the billionth of an amp draw from the insurance dongle, but the Jag can't? Call the dealership back. "We're so sorry must have been a defective battery." Bring it back to the dealership. They swap batteries allegedly. I bring the car home park it in the garage and one week later...dead again. Call the dealership, bring it back. After a week they tell me the insurance dongle is not letting the car "go to sleep" and must be draining the battery. Whatever, take the dongle out and bring it home. All is good no more dongle. 3 days later...dead. Back to the dealership, seriously, and after another week they tell me everything checks out ok and they have no idea whats wrong and the car starts just fine. So what can I do? Nothing but pick it up. Drive it home. 3 days later and it works! I take it to DMV to get it inspected no problems. Go home park it and 4 days later...dead again. I'm bringing it back this week.
Does anyone have any clue why batteries would keep getting shot like this. They claim my alternator is good and they have checked it 3 times now and I'm sure they'd be happy to charge me for a new one since the car is now out of warranty. I read somewhere that there are 2 batteries in the 2016s, one for starts and the main one. Is that true? But when I say the car is dead, its dead. Not even the LED dome lights come on. Plus it takes a long time charging it off my truck to even get it to try to start. Is there some relay that gets smoked after too many low voltage events or something? The dealership seems to have no interest in fixing this but if I bring it to another one I just don't want to go through the same disaster. Assuming they actually changed my original battery, I cannot believe I got 3 bad batteries in a row. There is nothing plugged into the car to draw power. For the first 4 years we had the car, I could let it sit for two months or more with no battery tender (I know not the best idea) and it would start with no issues. Since the original battery died, it will not last for more than a few days before it is dead again. Any thoughts or suggestions would be greatly appreciated.
Does anyone have any clue why batteries would keep getting shot like this. They claim my alternator is good and they have checked it 3 times now and I'm sure they'd be happy to charge me for a new one since the car is now out of warranty. I read somewhere that there are 2 batteries in the 2016s, one for starts and the main one. Is that true? But when I say the car is dead, its dead. Not even the LED dome lights come on. Plus it takes a long time charging it off my truck to even get it to try to start. Is there some relay that gets smoked after too many low voltage events or something? The dealership seems to have no interest in fixing this but if I bring it to another one I just don't want to go through the same disaster. Assuming they actually changed my original battery, I cannot believe I got 3 bad batteries in a row. There is nothing plugged into the car to draw power. For the first 4 years we had the car, I could let it sit for two months or more with no battery tender (I know not the best idea) and it would start with no issues. Since the original battery died, it will not last for more than a few days before it is dead again. Any thoughts or suggestions would be greatly appreciated.
Member
Joined: Jan 2020
Posts: 64
Likes: 33
From: Minneapolis/St Paul
You'll find battery problems on all the forums; it's a Jag universal. Here's what I know works on XK8s:
1. Use an AGM battery. I got mine from Costco for $200.
2. Keep a charger/maintainer on the car when it is parked overnight.
3. When the car is sitting, turn off all loads, close the windows and top, and LOCK it. If you don't do all this, the car will never go to sleep but will draw lots of juice and run down the battery.
4. Even doing 1, 2 and 3 doesn't guarantee you won't get spurious error msgs. Use an OBD scanner to clear them. I keep mine in the glovebox.
5. You might even need to disconnect the battery ground cable to clear some error msgs. I keep a wrench in the boot for just that.
Our cars are very touchy about voltage. I think it's due to the digital CAN stuff combined with ignition noise and other interference. Don't know if Jag ever did fix it.
1. Use an AGM battery. I got mine from Costco for $200.
2. Keep a charger/maintainer on the car when it is parked overnight.
3. When the car is sitting, turn off all loads, close the windows and top, and LOCK it. If you don't do all this, the car will never go to sleep but will draw lots of juice and run down the battery.
4. Even doing 1, 2 and 3 doesn't guarantee you won't get spurious error msgs. Use an OBD scanner to clear them. I keep mine in the glovebox.
5. You might even need to disconnect the battery ground cable to clear some error msgs. I keep a wrench in the boot for just that.
Our cars are very touchy about voltage. I think it's due to the digital CAN stuff combined with ignition noise and other interference. Don't know if Jag ever did fix it.
Last edited by Potvinguy; Dec 3, 2020 at 10:14 PM. Reason: nice
Senior Member
Joined: Feb 2019
Posts: 439
Likes: 121
From: Bay Area CA
I've been sifting through the threads trying to find one that details running the charger lines but haven't found one yet. When you say the charge point under the trunk floor, are you talking about the points on the battery terminals or somewhere else? Where does the connector exit the car? If you're going through the trunk do you have to let it get pinched in the trunk lid when you close it?
https://www.jaguarforums.com/forum/f...tender-209858/
Mine isn't exactly the same (I didn't install a port like the image in the thread), but it sticks out of a hole which I found in the front of the trunk. So the connector sits inside the trunk permanently. I can open the trunk to connect it and then close it with the wire sticking out.
Junior Member
Joined: Jun 2019
Posts: 5
Likes: 0
From: Newton, MA
You'll find battery problems on all the forums; it's a Jag universal. Here's what I know works on XK8s:
1. Use an AGM battery. I got mine from Costco for $200.
2. Keep a charger/maintainer on the car when it is parked overnight.
3. When the car is sitting, turn off all loads, close the windows and top, and LOCK it. If you don't do all this, the car will never go to sleep but will draw lots of juice and run down the battery.
4. Even doing 1, 2 and 3 doesn't guarantee you won't get spurious error msgs. Use an OBD scanner to clear them. I keep mine in the glovebox.
5. You might even need to disconnect the battery ground cable to clear some error msgs. I keep a wrench in the boot for just that.
Our cars are very touchy about voltage. I think it's due to the digital CAN stuff combined with ignition noise and other interference. Don't know if Jag ever did fix it.
1. Use an AGM battery. I got mine from Costco for $200.
2. Keep a charger/maintainer on the car when it is parked overnight.
3. When the car is sitting, turn off all loads, close the windows and top, and LOCK it. If you don't do all this, the car will never go to sleep but will draw lots of juice and run down the battery.
4. Even doing 1, 2 and 3 doesn't guarantee you won't get spurious error msgs. Use an OBD scanner to clear them. I keep mine in the glovebox.
5. You might even need to disconnect the battery ground cable to clear some error msgs. I keep a wrench in the boot for just that.
Our cars are very touchy about voltage. I think it's due to the digital CAN stuff combined with ignition noise and other interference. Don't know if Jag ever did fix it.
Believe it or not, my car would never go to sleep even tho did all you say in 1,2 and 3. So, until I figured out problem Was with multi CD player, disconnecting battery was only way I could stop battery from going dead.
Veteran Member
Joined: Jan 2010
Posts: 4,802
Likes: 1,773
From: Southampton, UK
F-Types are not XK8s. Mind you, the XK8, and subsequent 4.2 and 5.0 XKRs I had, never had any electrical issues, certainly not the "Jag universal" that you assert. Just my experience over 13 years of Jag ownership, so obviously not typical?
Senior Member
Joined: Apr 2017
Posts: 202
Likes: 14
From: Lake Forest, Illinois
Thank you for taking the time to reply sov211. I perhaps didn't make it clear that according to the dealership, I had 2 new batteries installed in my car. Its about an hour and a half from the dealer to my house and perhaps not enough to fully charge a battery, but seems respectable. Presumably the battery they took off the shelf, after who knows how long, was good enough to start the car at the dealership, I'd think an hour and a half trip would recharge it after a start. That I got 4 years out of my original battery is noteworthy, but that battery stopped being the problem when they took it out and replaced it on my first trip. As to the insurance dongle, it tracks only the mileage driven and discounts my policy since I don't drive the car daily and don't put much mileage on it. You should look into it, might save you some money. The point of mentioning the dongle was that it wasn't involved in the original battery going dead because I didn't have it then, and if it was involved in the first new battery going dead, it was removed before the second new battery went dead and therefore couldn't be the cause of the second new battery going dead. I'll have to watch for read traingle staying on after the car is shut off. So the last go round, it actually got me home from the dealership, sat a few days, and then got me a day out doing errands, then sat for a few more days and then died. Are these new batteries that finicky? One would expect the battery to be charged sufficiently since it was performing just fine for about 6 trips over the course of a week before suddenly deciding to die.
Anyway, thank you for the info.
Anyway, thank you for the info.
Senior Member
Joined: Feb 2017
Posts: 315
Likes: 61
From: Palm Beach Gardens, FL
I'm trying to fully understand the issues discussed above for an F type. First off, background. I don't understand some of the 'must do' warnings. I have NEVER done any of them. I disabled the auto-restart system (by disconnecting the small battery) shortly after acquiring the car - AC systems in South Florida do NOT work well like that. I park my 2016 F type in my garage (in-service date April 2015). I rarely lock it when at home. I have only seen an issue of low voltage (shortly after acquiring the car years ago) pne time - I believe it was a textural message on the dash saying something. At that time, I believe all I did was put a charger on the battery to get it up to voltage. After I believed it was charged, I removed the ground, then reconnected. I don't remember doing that multiple times nor antics as a result. The message went away and I've never seen an issue since. In April of this year during my last in-warranty oil change visit - the dealership did all sorts of checks and replaced numerous things. One of the new items I got was an OEM battery (complements of Jaguar). Prior to then I had zero symptoms - the battery was fine. I was happy to have them give me a new once since I'm sure I was approaching end of life. As an FYI - engine compartment temperatures are the culprit to short battery life - AGMs do better and since ours are in the trunk, they last a long time.
I agree that any car should be able to recharge the battery within a short time (20 minutes is NOT short IMHO) - if not that's a **** poor design. I've never checked - however I'd bet our alternators are likely at 100 Amp capacity or greater. A nominal engine start is likely 125 Amps (can be more if cold conditions). This may vary some - but it's in the ball park. If it's cranking for 10 seconds (very generous), then that is a consumption of 1250 Amp-Seconds of energy. Likely at idle, there is not much excess alternator capacity (slow speed equals low alternator output) - but once you get going, my guess is that there are at least 20 Amps of excess generating capacity that goes to re-charging. 1250 A-S divided by 20 A is more like 60 seconds to recharge. This is a far cry less than 20 minutes, so my guess is that we're at or near nominal voltage certainly within 5 minutes if your engine is running at normal revs (not idle). Note I've not checked real data on this car (alternator capacity and/or excess current capability) - I'm simply using reasonable assumptions.
TO MY QUESTION - I'm trying to understand the red triangle discussion above. The discussions are a little cryptic. I'm trying to understand when is the red triangle on? Where is it on the dash (left/right/top/bottom/corner)? The discussion above implies it comes on normally for a period of time (15 minutes) then goes out. Can someone enlighten me further, please? I don't have an electronic copy of my manual handy. It is visible from outside the car looking through the rear windscreen?
thanks in advance
I agree that any car should be able to recharge the battery within a short time (20 minutes is NOT short IMHO) - if not that's a **** poor design. I've never checked - however I'd bet our alternators are likely at 100 Amp capacity or greater. A nominal engine start is likely 125 Amps (can be more if cold conditions). This may vary some - but it's in the ball park. If it's cranking for 10 seconds (very generous), then that is a consumption of 1250 Amp-Seconds of energy. Likely at idle, there is not much excess alternator capacity (slow speed equals low alternator output) - but once you get going, my guess is that there are at least 20 Amps of excess generating capacity that goes to re-charging. 1250 A-S divided by 20 A is more like 60 seconds to recharge. This is a far cry less than 20 minutes, so my guess is that we're at or near nominal voltage certainly within 5 minutes if your engine is running at normal revs (not idle). Note I've not checked real data on this car (alternator capacity and/or excess current capability) - I'm simply using reasonable assumptions.
TO MY QUESTION - I'm trying to understand the red triangle discussion above. The discussions are a little cryptic. I'm trying to understand when is the red triangle on? Where is it on the dash (left/right/top/bottom/corner)? The discussion above implies it comes on normally for a period of time (15 minutes) then goes out. Can someone enlighten me further, please? I don't have an electronic copy of my manual handy. It is visible from outside the car looking through the rear windscreen?
thanks in advance
Veteran Member
Joined: Jan 2010
Posts: 4,802
Likes: 1,773
From: Southampton, UK
The red triangle is in the hazard lights switch. It should be out when the car has gone to sleep, if it stays on long after the car should have shutdown (10 minutes?) then you have the OBD drain problem. Yes. you can see it through the car windows (side and rear).
Member
Joined: Jun 2012
Posts: 45
Likes: 2
From: St. George, UT
Better check this....
I'm hoping someone has some experience to help me figure out this recurring problem because the local "expert" dealership mechanics can't figure it out or, more likely, are not interested in figuring it out. So, I bring my car for service and when I pick it up it says "Low Battery Start your Car." I go inside and ask what they did to kill my battery and they said they probably just had the door open while they were servicing it too long etc and so on. OK fine, that was about a year ago and it was the original battery so (Car is 2016) so I don't think much of it. Drive the car a few times over through the year, no issues, starts right up. Let it sit for a little longer than normal earlier this year and the battery was dead. Jumped it and took it to the dealership for a new one. Dealer says they have to check everything (So they can charge me for it) and reports back that everything was good, alternator is fine and system seems good and I just need a new battery to the tune of $700. Play expensive games win expensive prizes. Drive the car home park it in the garage. Now I add the insurance company plug in to get a discount on my mileage. Go out 2 (Two) days later and its dead. Completely dead not sort of dead. Odd, because my 15 year old car with mystery age battery can handle the billionth of an amp draw from the insurance dongle, but the Jag can't? Call the dealership back. "We're so sorry must have been a defective battery." Bring it back to the dealership. They swap batteries allegedly. I bring the car home park it in the garage and one week later...dead again. Call the dealership, bring it back. After a week they tell me the insurance dongle is not letting the car "go to sleep" and must be draining the battery. Whatever, take the dongle out and bring it home. All is good no more dongle. 3 days later...dead. Back to the dealership, seriously, and after another week they tell me everything checks out ok and they have no idea whats wrong and the car starts just fine. So what can I do? Nothing but pick it up. Drive it home. 3 days later and it works! I take it to DMV to get it inspected no problems. Go home park it and 4 days later...dead again. I'm bringing it back this week.
Does anyone have any clue why batteries would keep getting shot like this. They claim my alternator is good and they have checked it 3 times now and I'm sure they'd be happy to charge me for a new one since the car is now out of warranty. I read somewhere that there are 2 batteries in the 2016s, one for starts and the main one. Is that true? But when I say the car is dead, its dead. Not even the LED dome lights come on. Plus it takes a long time charging it off my truck to even get it to try to start. Is there some relay that gets smoked after too many low voltage events or something? The dealership seems to have no interest in fixing this but if I bring it to another one I just don't want to go through the same disaster. Assuming they actually changed my original battery, I cannot believe I got 3 bad batteries in a row. There is nothing plugged into the car to draw power. For the first 4 years we had the car, I could let it sit for two months or more with no battery tender (I know not the best idea) and it would start with no issues. Since the original battery died, it will not last for more than a few days before it is dead again. Any thoughts or suggestions would be greatly appreciated.
Does anyone have any clue why batteries would keep getting shot like this. They claim my alternator is good and they have checked it 3 times now and I'm sure they'd be happy to charge me for a new one since the car is now out of warranty. I read somewhere that there are 2 batteries in the 2016s, one for starts and the main one. Is that true? But when I say the car is dead, its dead. Not even the LED dome lights come on. Plus it takes a long time charging it off my truck to even get it to try to start. Is there some relay that gets smoked after too many low voltage events or something? The dealership seems to have no interest in fixing this but if I bring it to another one I just don't want to go through the same disaster. Assuming they actually changed my original battery, I cannot believe I got 3 bad batteries in a row. There is nothing plugged into the car to draw power. For the first 4 years we had the car, I could let it sit for two months or more with no battery tender (I know not the best idea) and it would start with no issues. Since the original battery died, it will not last for more than a few days before it is dead again. Any thoughts or suggestions would be greatly appreciated.
My 2000 XJR exhibited similar, no-start condition after sitting for awhile. Neither the dealer or an independent Jag mechanic had any clue. Finally, while inspecting in and around trunk where the battery lives, the indy mechanic happened to jiggle the the negative grounding cable as the car was running and it stalled.
Further inspection found that the new-looking ground cable was several corroded internally. Somehow moisture or other liquid had migrated into the cable and rotted it out. Anew one was installed for $70 and since then, new starting, running or other issues.
You might just check. Sometimes the least obvious things can cause problems.
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Joined: Aug 2018
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From: Exit 30 in NorthWest NJ
I'd bet our alternators are likely at 100 Amp capacity
And, I think that the genius that mentioned poor connections between the rear-mounted battery and the engine bay (which run along the bottom of the car, to the right side of the drivetrain) might be onto something. A high resistance could be messing up the car's electronics in that they can't accurately measure or determine the power to various modules. We saw a little bit of corrosion at our F's forward connection (where the big, fat red main power lead terminates) and took care of that last year.