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I am a very new XF owner and love the car. Only problem is something is killing the battery.
It is being flattened every two days even when driving, Halfords checked the battery on their matching and seemed to think the alternator was working fine.
My smart key is not working properly and I am using the fob dock to operate the car and leaving it unlocked.
This is about all the info I have.
Could anybody have any ideas of the best place to start?
What is the voltage across the terminals, with the ignition in the off position for ten or more minutes, when measured with a voltmeter? Must be a minimum of 12.6 volts for the vehicle to function properly.
With the engine running, what is the alternator output to the battery? You can check it with a Bluetooth wireless reader through the OBD port and the Torque app on a smartphone. Should be 13.8 or so with the engine at idle.
I say this cautiously but XF seems to be running fine now so I have a possible theory.
When the old battery went flat and the warning light first came on I changed the battery the next day for a new one. Later that day I noticed the warning light first on the centre console system as a red triangle then I say it on the dashboard behind the steering wheel. I pressed on the red triangle on the centre touchscreen and cleared the warning. £ days later and I have not seen a warning anywhere since.
So my question is this;- Could it simply have been the fact that I never cleared/reset the original warning and so it was still showing up there even after I had installed the new battery?
What is the voltage across the terminals, with the ignition in the off position for ten or more minutes, when measured with a voltmeter? Must be a minimum of 12.6 volts for the vehicle to function properly.
With the engine running, what is the alternator output to the battery? You can check it with a Bluetooth wireless reader through the OBD port and the Torque app on a smartphone. Should be 13.8 or so with the engine at idle.
Andy Brown, sorry for butting in - just have a quick question for NBCat.
Hi NBCat,
I never knew Torque can show the volt output - happy I noticed your post mentioning this.
Which one is the correct selection though? I noticed that the Torque app has 2 options... Volts(Ad) and Volts(CM)
@mrNewt There are two ways to check the voltage on Torque: OBD Adapter or Control Module. Generally, one would use the OBD adapter that's plugged in, but bear in mind that the voltage shown through the OBD adapter, or even the Control Module may differ from what the voltage is at the battery.
For the most accurate reading, it's best to check the voltage at the battery as it's connected directly to the alternator. Using the Torque app is a way to tell at a glance if the alternator is functioning or not.
@Andy Brown, did you check the voltage across the battery terminals with a voltmeter? If so, what is the reading with the engine running at idle and with the ignition OFF for ten or more minutes?
Thanks NBCat but I am the least technically minded guy there is - so I got a mechanic to test and he confirmed all is ok with alternator, sorry I cannot answer your specific question as that's all I have.
Just wondered if my theory of the warning being an uncleared/leftover one from the original battery dying could actually have any credence to it?!
@mrNewt There are two ways to check the voltage on Torque: OBD Adapter or Control Module. Generally, one would use the OBD adapter that's plugged in, but bear in mind that the voltage shown through the OBD adapter, or even the Control Module may differ from what the voltage is at the battery.
For the most accurate reading, it's best to check the voltage at the battery as it's connected directly to the alternator. Using the Torque app is a way to tell at a glance if the alternator is functioning or not.
Thanks NBCat but I am the least technically minded guy there is - so I got a mechanic to test and he confirmed all is ok with alternator, sorry I cannot answer your specific question as that's all I have.
Just wondered if my theory of the warning being an uncleared/leftover one from the original battery dying could actually have any credence to it?!
Ps MrNewt - no worries at all
Certainly a possibility, but it's good to periodically check the system's performance.
Andy see if there is anything plugged into the OBD 2 port if so take it out I had one of those Verizon HUM engine scanners plugged into my 2010 XF full time and it trashed 2 batteries before I was told by a Jaguar mechanic that the cars computer would not ever go into sleep mode and stay active 24/7 killing the battery
I am a very new XF owner and love the car. Only problem is something is killing the battery.
It is being flattened every two days even when driving, Halfords checked the battery on their matching and seemed to think the alternator was working fine.
My smart key is not working properly and I am using the fob dock to operate the car and leaving it unlocked.
This is about all the info I have.
Could anybody have any ideas of the best place to start?
Battery Help!!!
- just have a quick question for NBCat.
