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Morning,
I've had ongoing issues with my battery going flat. I've had the car 3.5 years and am on my 3rd battery. Until recently, no-one has been able to find any draws on the battery that could be causing the battery to go flat.
I've just had it with my 3rd Auto Electrician and they've diagnosed a fault with the Body Control Module (BCM). This has been replaced and now only drawing 0.01amps when car is off. However, after replacing the BCM, the radio controls on the steering wheel don't work, the GPS doesn't work and the Reversing camera doesn't work. This is an after market stereo so has always been my concern that this has been causing my issue but no-one has been able to say for sure yes or no.
How do you test/know that a BCM is having issues? How do you know that draw on the battery is resolved if everything that was connected is no longer connected. Would the 3 things that aren't working normally be connected/controlled by the BCM?
My concern now is that once these items get connected again, I'll back to square one with a battery drain.
Any help/advice would be greatly appreciated.
Cheers,
Frustrated Owner!
Hello I have spoken to a Mazda parts supplier and have been told the you must ensure the numbers all match up on the BCM, if the BCM isn't compatible some functions may not operate.
Or check simple things like all the plugs are plugged in and no fuses are blown I would take it back to where it was repaired, when I used to do voltage draw tests I would unplug fuses to find which circuit was drawing voltage,
BCM modules add another layer of complexity as they are a all in one unit that cant be easily tested.
In my experience is that aftermarket components tend to be the culprit in voltage draw scenarios, it also may pay for the electrician to take a close look at the way the stereo unit was wired in.
Thanks for the reply. I believe the Auto Electrician is aware that the numbers should match as the first one they sourced was incorrect.
I'm booked back in on Wednesday for them to reconnect (if possible).
However, I've paid for a new BCM. If everything isn't connected to the new BCM that was connected to the old BCM, how do they know if the BCM is at fault?