2003 Tahoe "rear access open" message

[James417]

My 2003 Tahoe has a rear access open message on my dash when the rear access is obviously shut tight. I cleaned the contacts and got them nice and shiny. Still says rear access open. Removed the contacts to look at them and test with multi meter and they where fine. So I'm thinking loose connections or BCM is acting up. I also have the lights stay on inside so I have to use the dome light override to stop that from killing my battery. Then when it randomly acts up and thinks the rear access is open if my rke alarm is set the alarm goes off thinking the doors open. And this happens at random times of day and night. Not only does it piss my neighbors off it also kills my battery. I also had my whole dash cluster die completely on me once. Nothing was working like no signal going to the dash cluster and the wipers and lights where acting weird. Then the battery again died and once recharged it was OK again, Just the random rear access open message again. So probably bad BCM but any connections I can check? I had my alarm go off 3 times in 30 minutes a little while ago and I'm ready to fix this because it getting pretty bad. Thanks in advance

 

[James417]

Still does this. Any suggestions for connection and ground problems I can check before I buy a new BCM? Also the front doors locks operate as they should. With the rke and push button electric locks they unlock and lock. But the rear passenger doors and rear access doors only lock but won't unlock? I have to do these manually when I unlock them. Maybe its the lock actuators but its kind of strange they would all stop unlocking like that in the rear at once.

 

[Sub]

I have found that I need to really "slam" the rear hatch closed, otherwise only one of the two latches will engage. When only one latch engages, the rear door feels shut tight, and appears to be shut tight, but the dome light remaining on is my clue that the other latch didn't quite engage.

On mine, it is typically the passenger side lower latch that doesn't quite shut. I reason that this may be due to my always closing the hatch with my left hand, because I'm carrying something with my right hand.

Despite knowing that my hatch has this characteristic, I have been fooled more than once by my hatch appearing and feeling shut, while not actually being fully slammed shut.

Not sure if this is helpful for your situation, but it is what ended up being the issue in my vehicle when I experienced similar symptoms as you describe.

 

[Granprixfan]

I too have been having the DIC display rear left door ajar and my alarm doing same thing you describe I had been manually locking to remain a good neighbor (but recently got broken into.. Rotten luck whilst alarm not functioning)
In my case I am certain that the BCM is out;
I checked the connections like you did
Pins are not corroded from detailing carpet
Open and close circuit readings from doors at pins/point of connection to BCM read as they should Have you done this?

But you say;
That rear doors only lock and they don't unlock for you correct?
The actuators are working they are not the problem they are just not getting the reverse polarity

There is the possibility that it could be the combo switch in drivers door
I'm passing this on to you as was suggested to me by mechanics at my work when diagnosing my Yukon as they have had these go out on the cops Yukons they've worked on and
It's much cheaper than a BCM
That's not to say it's definitely the switch
The switch "runs through " the BCM
But I just picked up a new ACDelco BCM and they are not cheap!
Oh you also asked about ground issue being possible
Could be
I believe the BCM is grounded at the firewall in the engine bay by a braided wire to a stud just left of brake master easily Accessible