2003 Hummer H2, picked up about a year ago and it's been a year long project basically rebuilding the whole drivetrain. Not to mention replacing all sensors and whatnot, including the fuel pump. Throughout this saga, I had the rear hatch ajar periodically. Cleaning up all the grounds seem to take care of that for a month or two. It came back with a vengeance. I went ahead and cut the pink wire about 4 in from the BCM plug. A week later the light came back on. Pulled the BCM, cleaned up the circuit board. Re-soldered a few spots. Removed the capacitor for the rear hatch a jar signal, I could care less if that's monitored. And a week later... It lit up again! That could only mean somewhere on the circuit board there's a random short to ground in that circuit, activating the message. For 2 weeks I discovered I could reach under the dash and that bottom plug... If I pushed it in firmly the message would go out. Got to be an everyday ordeal.

Went ahead and ordered a refurbished BCM, programmed with my VIN. Saturday I will be installing, and performing the passlock relearn.... Same as when I redid the ignition. With a new passlock sensor.

The good news I guess, is that when I dove in to remove this one, I discovered the previous owner had made a cutout behind the instrument cluster to make it easy.

After I get the replacement installed, I will post the results... And if it works according to plan, I'll post the link to the source I used. It arrived in this morning's mail, surprisingly quick from Ohio to Oregon.... And I ordered it Sunday afternoon. We will see if this ends of the saga of the BCM...

​​​​​

 

if force corrects the issue then you might have bad /loose/ corroded pins on the harness connector or maybe loose pins on the bcm.

 

Yes, I checked the connector as well as the pins where they're soldered on to the circuit board. I figured when pushing the plug in with a little bit of force it flexes the circuit board. The liftgate ajar is signaled by a ground connection... So the short has to be somewhere between the capacitor right next to the pins, and the chip itself.

Lol .... I'm starting to believe in H2 Gremlins.... It hasn't triggered the message since I ordered the refurbished BCM. (3 days) It's like it knows....... I'm sure Stephen King would concur, LOL

 

if it is a Surface Mount Capacitor (small brick looking) tantulum capacitor then it might be bad or going bad. they tend to short when failed.

 

I completely desoldered and removed the capacitor because I don't care about the rear lift gate ajar message. And wouldn't you know it came on the next day. Interestingly, pushed up on the plug and the message went away. And since then it's been bitterly cold and dry.... 2 weeks now without the message. So I'm thinking humidity is just enough to trigger it somewhere on the circuit board.

Didn't get around to put in the new BCM in yet..... Been getting over a nasty cold..... Heating up the shop this weekend to attack it.

Also there's no water intrusion anywhere under the dash. Even check the splice connector. Bone dry with no sign of corrosion.

 

Digging into it today. Really appreciate the previous owner.... Obviously had the BCM repaired or replaced before, put a nice cut out behind the cluster to make it easy. Literally 15 minutes to get the BCM out. Priceless

 

Halfway in.....

 

And 5 minutes to tuck it back in and plug everything in. It made the BCM swap a 30 minute ordeal while drinking my coffee. If I was in a hurry I could probably do it in 20 minutes. What's the normal shop right on this? Something like 6 hours? OMG

 

Awesome. The following link is the source for the outfit I purchased it from. My erroneous ice possible and rear hatch ajar is solved. Price was $350, you send them your VIN and they program it in. You don't have to send your old one in. The outfit has a presence on eBay, the link follows, or you can purchase through their website.

https://www.ebay.com/itm/25616988710...emis&media=SMS

 

Thanks for the write up.
I’ll saving the link for the BCM as we know now it’s a trusted source.