I have a 2005 XK8 and am having a couple small issues, the heated seats don't work (light doesn't come on the button) and the windows go down slightly when the handle is pulled, but then goes back up when handle is released, so I have to hold the handle up to close the door (obviously supposed to stay down slightly until door is closed). The BCM is the only thing I can think of that might cause both of these issues. It is possible that the issues aren't connected at all, anyone have any ideas of what to check before the BCM? Thanks!

 

First check the voltage across the battery terminals after standing for 30 minutes with ignition off. You are looking for ~12.6V. If it's much lower than that, then either battery needs to be charged, or it is suspect.

Do a hard reset*. Member Gus explains how, with pictures:
JagRepair.com - Jaguar Repair Information Resource

and see attached for what to do afterward hard reset.

If that doesn't have any effect on the window operation, it could be that the car doesn't know if the door is open (latch microswitch). Does the puddle light come on when you open the door?

The BPM is unlikely to be related to these issues.


*unless you have a smog test due in the near future, in which case delay until afterwards.

 

BCM is probably not the problem.

The door modules or latch switches are likely faults for the windows.

Seat modules are likely faults for the seat heaters.

Battery is always suspect as michaelh stated.(always verify FIRST)

 

Looks like battery is at 12.3V and I'm not seeing any puddle lights when I open the door.

 

When you have issues like this the best thing to do is pretend you don't have any mysterious black boxes to blame, and imagine you are working on an old MG. What would you check on your 1976 MG, if for example the light didn't come on when you open the door?

 

How do you check seat module for “no heat” situation?