nxtkitt

Alarm was working fine with original BCM but BCM was starting to fail. Courtesy lights stopped working, it had a short in it somewhere too. Replaced it with my old BCM (same year car which ALSO had factory alarm) now the car doesn't recognize having a factory alarm when i try to program it. (no chimes when i push key FOB in programming mode). Everything else works fine. Even tried it with the door shut before turning key to ACC. Any ideas?

xephona

iTrader: (4)

OOOO another WI person! Well... I just did a BCM swap in my car, so maybe I can help a bit (with some more info of course). What year car are you working with? Are you actually getting INTO the programming mode?

nxtkitt

it's a 96 TA. Original BCM (now in THIS car) came from a Formula. I AM getting into programming mode- i can change other functions, but it will not respond to the key FOB or pushing unlock on the door while IN programming mode...??

xephona

iTrader: (4)

You did sync up the key fob to the "new" BCM ... correct? And... working batteries are available I assume?

EDIT: And a final thought is... the chimes actually work... right? I know a few people on here disabled the chimes by pulling parts out of their BCM. A quick test would be to put your key in the ignition with the door open.

nxtkitt

yes, it's sync'd up. i can use the key FOB to lock/unlock just fine.
the chimes work when i'm in the other programming mode, so I know they work

it's strange - this BCM worked fine in the original Formula. And the alarm worked fine in both cars. It just decided to not work in this TA body...

xephona

iTrader: (4)

Well for the moment, I am all out of ideas on that situation then.. crazy confusing. However, if you still have the BCM for the TA with the broken lights... then you should open it up and look at the chip inside. There was a writeup on her about "why" they break, and how to fix them. It very well might be easier to open it up, look for cracks on the chip, and try to repair them. That SHOULD solve this little problem without any more troubleshooting. I will edit this post with the link in a sec.

EDIT: Here is the link to the post, some of the stuff is "deleted" but you can still view it all (minus the pictures) from the quotes. https://ls1tech.com/forums/general-l...blems-fix.html

Basically.. it says to look at the board inside the BCM for some hairline cracks along soldier joints, and re-soldier them if broken.

RjackTA

Did you ever figure this out? I just ran into same problem.
Replaced BCM with new from GM....now no alarm recognition.
I get 2 chimes in program mode but cant program alarm features.
Key fobs work.