"line out converter fried my BCM"

[zcs626]

Took my car in because the TPMS light was on, along with this list of non-working amenities:

-power locks-power windows-power seats-sunroof-turn signals-hazards-power trunk

Get a call from the dealer, and they say "whoever installed your audio system fried your BCM."

I am a MECP certified tech for over 5 years now, and know what I'm doing. All i have in the car is a 4-channel amp and 4 speakers, thats it.

The tech claimed that the line-out-converter (LOC) wires that come out of the LOC itself, were pulled out of its original location, and because the speaker wires coming out of the LOC must have somehow touched something causing the BCM to fry and pop its 40amp fuse.

I know that if speaker wires touch together, the only thing it will do is turn the amp into protection mode.

Anyway, the tech says that Nissans R.A.P. wire (retained accessory power), is tied into the speaker wires "somehow" (that was his exact word) and caused it to fry to BCM.

I think personally he is trying to screw me over, saying that he will not charge me for the new BCM, but just the labor to figure out what the problem was. At $95/hr for the 3 days he had it, my wallet isn't going to like that.

Does ANYONE have any hard evidence or something that I can give the service manager proving that the TPMS light coming on was the procuring cause for the BCM to fry? I've read several cases about TPMS lights, etc; but nothing that I can use as grounds to not have to pay for the labor dollars he took work on the car. Sorry for the hella long post.