Just got a '04 H2 with leaks i didn't know of. All started when i went to vacuum it and noticed a puddle under the floor mat from the carpet. Driver's A-pillar leak. At the same time it has done something to my Sensing and Diagnostic Module (SDM) of the Airbag found under my driver's seat. So apparently the leak has reached it or affected it in some way. Took it to the Dealer and he said the whole vehicle had been submerged under water but it hasn't i have checked the rest of the truck. He figured i didn't know much about what was going on with it.....i guess. I informed him of the common leak and said that's where it came from and he then knew that i knew what i was talking about. Anyway, he said they wanna replace the SDM and clean the pins to the connector. He said parts and labor $1600. I'm mechanically inclined and my father is a Master mechanic...is that alot. Can i find the SDM cheaper somewhere? Should i try to clean the pins and connector first? I've been research the leaks and bought the Black RTV adhesive sealant that everyone suggests and sealed the corner cab light. I'll test it with the water hose in the morning hopefully the leak is fixed. What are your opinions, advice, suggestions as far as the SDM under the driver's seat. As of now the airbag light stays on. Guy at the dealer also said if i spent the $1600 it don't guarantee to fix it, just a start in case something else is wrong. (Sigh) i'm exhausted with this already. Like the truck but not the happiest person right now.........man.

 

I've seen a lot of posts about leaks and have some myself.

But.... I've never even heard any mention this SDM thingy.

Not saying it isn't a real issue. Sounds like a BS money grab to me.

Have you tried unhooking the battery cables and tie them together with nylon ties and let it sit for 1/2 hr. This will drain the caPacitors holding memory.

Get a second opinion.

See what your dad thinks.

 

$395 from here
2004 Hummer H2 Parts - MileOneParts.com

I would try disconnecting the battery (like Madmayo said) first.
What alerted you (other than puddle) that the SDM was malfunctioning?

 

2004 Hummer H2 Parts - GM Parts Department: Buy genuine GM auto parts & aftermarket accessories at wholesale prices.


300 here


just more info or same as dealer here http://workshop-manuals.com/hummer/h...tem_diagnosis/

 

guess I should have mentioned the leak its probably the roof marker light they all leak sooner or later, remove the corner ones (yellow) and clean thoroughly then silicone where wires go into body through rubber plug I siliconed the rubber plug into place and where the wires go thru it etc you will see exactly the problem when you remove light lense, also sunroof seals are known to leak, look where the water flows to drains and make sure all the tracks are clean they get filled with muck over the years, theres tons of write ups on the leaks subject

 

pull the drivers side pillar kick plate, and pull back the rug, you will find a sunroof drain tube there.. make sure it is going through the floor.... drove me crazy trying to do marker lights until I was going to pull out the rugs to clean and dry 'em... yes my SDM is also done for, it is placed under the seat and the rug exposing it to moister....

 

yoymon,could you please tell me how to remove the front sidelights ? I have the chrome guards over the lights, and can't see any screws,I do see a large opening at the rear of the light that looks like I should fill with silicone as it runs into the bottom of the lights, would that help ?