2017 S Convertible
1. Went to start yesterday and the dash lights came on but no turnover/no start. Red hazard triangle was on but it has not been connected to a code reader recently and I did not notice it being on when I walked past the car several times over the weekend. For the heck of it disconnected and reconnected the battery with no effect. What else could cause the hazard triangle to come on - and battery to be low? It sat for the weekend but all normal before that.
2. Connected CTEK. Charged fine. Battery is a year old, Interstate Group H8(49) AGM 36.
3. Tried to start after charging - dashboard lights came on, no turnover, dash lights flickered a bit and everything went off. But (I think) red triangle was on again.
4. Thought I would try battery disconnect which I did. Then, like the idiot I am, closed the trunk.
5. Jumped it hoping I could at least open the trunk but this did nothing. So right now it is a brick.

Given the red flasher light being on, I assume there is drain/short somewhere.
Any thoughts, suggestions would be much appreciated. Any way to open the trunk? Remember this is a convertible.

Thanks for reading.

 

Assuming that the doors are not locked, you can open the hood/bonnet and connect a battery charger (yes, even the CTEK) to the + and - points on the right/ passenger side at the front (the box with the red and black caps). + to the point under the red cap, negative to a bolt stud further back (that is toward the cabin).

This charging should permit enough power to allow you to open the trunk.

The fact that your battery is only a year old means nothing. Your usage of the car intermittently (plus the likelihood that a device has been connected but not shut down properly before disconnecting) has allowed the battery charge to drop. The battery itself may be faulty. Modern batteries can often appear healthy but fail when under load (from the starter motor).

The CTEK unit is not a battery charger in the normal sense. It is designed to be used to maintain battery charge while the car is not in use, and to be left connected. For the last 6 years my car has been connected to the CTEK unit when the F-Type is not in daily use. Result: zero issues. Infrequent use of the car plus short runs = starved electronic modules. This is by no means restricted to Jaguars. Every luxury car manufacturer sells the CTEK units under their own label for the same reason.

 

Thanks for the comments. I did try jumper cables with no luck. Is this because the battery positive is disconnected - remember I did that because of the hazard triangle only intending to lower, not close the trunk. My mistake.
I do use the CTEK occasionally but maybe not enough.

 

You need a connected battery for the underhood terminals to work. I think I recall some years ago someone managed to apply power by getting under the rear of the car and finding a suitable positive connection to attach to, any ground will suffice, of course.

 

I figured the disconnected battery was going to be a big problem. Thanks for the tip about a positive lead underneath. Will check that out.

 

You should be able to connect a battery or a dumb battery charger (NOT a CTEK, etc.) to the jump points under the hook. A battery maintainer needs to detect a connected battery before it turns on, which you don’t have.

 

Good point about not using the CTEK. I tried jumping it with no luck but the cables I borrowed were a little suspect. And I do wonder about the disconnected battery as scm pointed out. My cables, of course, are -- in the trunk, along with the CTEK so can't use it anyway. This is almost funny. Almost.
But DJS and scm, thanks again for the comments.

 

BTW, in the future when you've sorted this, it's only the negative terminal you need to disconnect to restore the system if the red triangle is on.

 

Found this on an older thread from a8Silver: Too bad he never posted pictures like he stated he would. Would make your job a lot easier. Maybe you can figure this out?

I was able to get the trunk open by applying fused 12V to Pin 6 (Black wire) on the C3BP01F connector. It was the best clicking sound I have ever heard !!!!!!!!! I used the backup 12V battery from my garage door opener.

 

Rondog, thanks for researching this. It was on my list for the day but have not had time yet. Now I have to decipher A8Silver's post.

 

I was able to find A8Silver's post which had some good information in the replies.
https://www.jaguarforums.com/forum/f...attery-238629/
See Unhinged's - of course - comment in #7.

Also there was a link to the Wiring Quick Reference Guide:
https://www.dropbox.com/scl/fi/a1wz9...okt6r&e=1&dl=0
The connector he used is C3BP01F which is in the "Area 'C' Footwell" drawing.
But one question - what do I use for a 12V power source? I may be showing my lack of electrical knowledge but can the source be another car battery if the connection works? (I have not looked at the connector yet.)

Thanks again for the help.

 

Yes and no. A car battery would work, but it’s also dangerous as it can source an enormous amount of current - so if the connection weren’t right, it could cause damage.

You could use something like a 5A fuse in series with battery, for some protection. (I haven’t looked to see what fuse is used, but I’d guess that’s enough.)

You could use A8Silver’s approach and use a 12V garage door opener battery, though you’d have to attach wires.

I’m sure you could find a cheap 12V AC/DC power supply (“wall wart”) on Amazon, etc. You could just cut off the connector and strip the wires.

You could use a dumb battery charger, ideally one with a low current setting.

Know any ham radio operators? (I’m one.) We tend to have lots of 12V power supplies.

 

WOW, this sounds like rocket Science
In the past I've had a battery fail and needed to get into the boot. no big deal, I just used jumper cables to the engine jump posts from another car to power up (not start) and opend the boot.
Why is this so hard?

 

Because in your case the battery was just dead but still connected. In this case one of the battery leads is off the battery altogether so the circuit is open.

 

DJS, thanks for the suggestions. But life is never simple. When I looked at the fuse panel in the passenger footwell it looks nothing like the diagram for "Area C" in the Wiring Quick Reference. Mine is a normal fuse panel with a bunch of various fuses, a fuse puller and a couple of relays or connectors The diagram is from 2013 and I have a 2017 so I imagine that explains it. I don't find another panel similar to the one in the diagram. I am lost in a wiring diagram so cannot find the proper connector for the trunk. If anyone has the Wiring Quick Reference for a 2017S that would be good but I think I may be back to Unhinged's suggestion of accessing a cable in the front wheelwell.
Thanks to everyone for their thoughts/comments.

 

That's not how electricity works. My battery wasn't just dead it was really dead, would not even take a surface charge (open circuit as you say). The car doesn't really care where it gets the 12 V from, it just needs the 12v even if it is from the front of the car instead of the back. Using a replacement jumper battery at the jumper posts at the engine is replacing the battery so it doesn't need to be connected in back.
Other suggestions of crawling under the car or jumping into a fuse box or a cigarette lighter or whatever would be the exact same thing just not much of a good connection.

 

That goes against everything I know about electricity. With the cable off the battery, it's the same effect as cutting the cable. The circuit can't complete. It doesn't matter if you have remote terminals in the front of the car, you still have a break.

 

Well sorry to say you may not know enough about electricity. Not to put you down but take a look at what happens when you put two batteries in parallel. Doesn't matter if you cut one loose the other one is still connected in parallel. Semi trucks often have three batteries in parallel and sometimes one of them is disconnected or fails the only thing that happens is the starter motor won't crank over as fast. I am both a certified diesel mechanic and a certified electronics technician and I specialized in electrical for many years. Don't take my word for it just look up what happens with two batteries in parallel, not in series.

 

There isn't a second battery in the front. Just the one in the trunk, which is disconnected.

 

Correct, that's why you add the second battery in the front to replace the battery in the back (you cannot get to) with a pair of jumper cables from another car or battery.