When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
It could be a faulty BMS module which I've often thought is an unneccessary level of complication that adds nothing to the robustness or reliability of the battery charge state,
The BMS module can generate DTC's to help diagnose battery or generator power supply issues and Jaguar Diagnostics also has a battery and generator self test routine which could help pinpoint the cause.
It could be a faulty BMS module which I've often thought is an unneccessary level of complication that adds nothing to the robustness or reliability of the battery charge state,
The BMS module can generate DTC's to help diagnose battery or generator power supply issues and Jaguar Diagnostics also has a battery and generator self test routine which could help pinpoint the cause.
Graham
I saw something about that in the workshop manual. Is that the module connected to the negative battery terminal?
The car does seems to be running fine mechanically, my guess would be it’s something wrong with an electrical system or a component. I’ll have a search and see if the BMS has failed for anyone else.
I saw something about that in the workshop manual. Is that the module connected to the negative battery terminal?
The car does seems to be running fine mechanically, my guess would be it’s something wrong with an electrical system or a component. I’ll have a search and see if the BMS has failed for anyone else.
A
almost guarantee this is a wheel speed sensor or brake booster failure don't freak out, the TCU isn't getting the data it's looking for, just need to check things one at a time
Hi all, sorry for the delay in posting. It's been so manic since being back at work. Here's an update after my visit to the dealer.
The car went to the dealer on the 8th Jan. And of course there were no error messages coming up on the dash display even though I took the car for an extended run before I dropped it off. This is the first time it hasn't shown the messages in the best part of a month!
I asked Jaguar for a diagnostic appointment ONLY to check what error messages and codes the car had been throwing up. Cutting to the chase, the diagnosis from the dealer is that the error messages from the various control modules point to the Brake Lamp Switch (I think it's part C2P14525).
If you care to read on I have a bit more info and some comments and questions below:
They gave me an 8-page print from SDD which had every message from every control module and sub-system. This goes back to about 2016, there are no other faults prior to that. Is that a lot of messages? It's a lot more than I was expecting but I guess it depends what they actually say / point to.
Would the dealer I bought the car from used when it was 18 months old have wiped any previous messages? I assume that they would have?
I asked to speak to the chief tech direct and he walked me through the various messages and explained how the various networks in the car work and why he believes the control module messages point to the brake lamp switch. This all seemed to make sense, but wasn't exactly definitive!
I have had the car on trickle charge every day since and have driven it as much as I can. So far no error messages at all. I still need to take it on an extended run for an hour or 2. I am wondering if they didn't reset the car properly after the battery was changed? I will carry on monitoring the situation and then get the switch replaced in the next few weeks.
Thoughts and comments gratefully received and apologies once again for the delay in updating. I will post some extracts from the DTC reports if I can work out how to post the images.
Attached some screen grabs of the messages that Jaguar say point to the brake lamp switch. You can see from this that the messages aren't all from the same date. Last message was from the day I took it in but nothing came up on the display.
The car hasn't shown any messages for the last 10 days.
Andrew, I went through a similar issue with my car in November of last year. Diagnostics indicated several things, a bad negative cable which holds the module on it (one piece unit w/cable), a weakened battery (replaced) and a faulty alternator. Nobody asked the age of your car, but the bad alternator could have caused the negative cable and module to malfunction. Since being replaced, no more issues dealing with that. I did get other codes, indicating a bad evap canister.. Good luck.
Andrew, I went through a similar issue with my car in November of last year. Diagnostics indicated several things, a bad negative cable which holds the module on it (one piece unit w/cable), a weakened battery (replaced) and a faulty alternator. Nobody asked the age of your car, but the bad alternator could have caused the negative cable and module to malfunction. Since being replaced, no more issues dealing with that. I did get other codes, indicating a bad evap canister.. Good luck.
Thanks for the reply. Sounds like you’ve been on a similar journey. My car will be 7 years old in April.
I’ve replaced the battery and alternator. But not the negative cable I think that’s attached to the BMS as well?
01-06-2020, 01:07 PM
