I keep getting an alarm that rear access is open. Not a big deal but the air compressor won't run with a door open and the rear slowly drops down. I've traced the pink/black wire all the way back to bcm and determined the gate switches are functioning correctly. With either switch in the latched position I have grounded circuit, then open circuit when both latches are released. I finally cut this wire near the bcm and still get rear access open. If I wiggle the plug at the bcm, sometimes the alarm clears. Can I replace the bcm with another one from an h2? or does the donor bcm need my vin programmed? I'd like to avoid a $200 trip to dealer for something I'm not 100% sure on. thanks

 

As long as the donor one has the same options it will work fine without programming.... in other words you need to be sure the donor one comes from an H2 that also has the rear air ride. I think that is really the only main feature that will matter from a donor.

Aside from that you need to find the leak. The rear air ride should not go down on its own just sitting there ever. The airbags are reasonably cheap and are usually the most common part to go and not terribly hard to replace. Not fixing the leak is causing the compressor to have to run a lot more than it needs to which is extra wear on that. The compressor is not cheap... $800+. The bags are only about $100 each and generally last 10+ years.

 

Ok thanks. The service air suspension popped up once too. The system seems to function correctly. Are the aftermarket bags ok, or do I need Oem? They don’t look dry rotted.

 

I'd think aftermarket ones should be fine. It just should not leak down at all. If it goes down sitting overnight etc than there is a leak somewhere that really should be found and fixed.