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Discussion Starter #1
When I installed my Parrot Mki9100, I ran across an odd problem. The lighter and console power sockets didn't turn off when they should, which is when the doors are opened after shutting off the car. Instead, they stayed on until the 20-minute whole-car-shutdown timer elapsed.

At first, this was diagnosed as a stuck relay. But upon further examination, the car failed the final step of the procedure for diagnosing a Retained Access Power Malfunction, and the service manual said it was time for a new BCM. (This is because the BCM was failing to shut down the aux power relay when the door opened).

Curiously, a 2004 that was at the dealership at the time appeared to have the same problem. And, now that the new BCM has been installed, the car still fails the test leading to a "replace the BCM" result.

Well, it's pretty unlikely that 3 BCM's were all bad hardware-wise, and that the real problem is that the BCM firmware has a bug. Round 1 of my dealer's taking the issue up the line got back an answer of 'It's supposed to work that way'.

I've explained to my service manager that I don't accept that answer, and expect GM to either conclude that there is a firmware bug, or explain why 2 different BCM's fail the diagnostic procedure in the manual. We'll see what happens.
 

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Interesting problem but it begs the question: Does RAP work properly if you disconnect the Parrot?

It may be interferring with the low-speed bus, causing the BCM to hiccup. Since a lot of the troubleshooting procedures in the manual start with, "Are there any aftermarket devices installed?" this could deal the Service Manager a Get Out Of Jail Free card.

I agree, 3 bad BCMs are highly unlikely.

Whenever I troubleshoot anything, the first question I ask is, What were you doing when the problem began? The XLR is a great car --but not when it comes to electrical mods. I'd suspect the Bluetooth mod first and start troubleshooting from there (if they haven't already done that.)

Let us know how this one unfolds. . .

CC :seeya
 

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Discussion Starter #3
Well, first off, the Parrot does not connect to the class 2 bus. See the details at the other forum.

And the problem was diagnosed prior to my doing the install.

The 2004 at the dealership we checked at the dealership had no accessories; we plugged a phone charger into the lighter outlet and observed the little power led on it stayed on when it should not have.

See si document 1878051 and the wiring diagram 1902317.
 
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