If the seat had worked, but then failed it suggests a failure, perhaps an internal break in wire or possibly a broken/corroded Pin F (orange wire pair) on the adjuster connector meaning +12V would still go to the lumbar switch.

If it never worked (say not your truck) the possibilities are endless, although I notice the passenger switch has the same connector, but wired differently, can't imaging someone tried grafting one in.

Pin F?

 

Thanks for participating! Good guess, but NO!
Also, nobody monkeyd with the H2, as I have had it since almost new (was one the the 500 Special editions that were US dealer demos that GM used for 6 months and then sold).

No aftermarket stuff involved (very little of that on my vehicle).
Everything worked perfectly till this problem popped up when my wife went to manually move the driver seat (via side seat switch) forward. (Right side works perfectly on all functions.)

Hint #1: The answer is much simpler technically than you are looking at. In fact, it was so simple, that I could not have thought anything like this could possibly happen, so I left it till last to check.

Huge Hint #2: Problem was "related" to the PCB board in the seat-side switch assembly.
All functions on the PCB board worked as designed, ie. the board was not faulty.
The connector to the PCB board was good, powered up board correctly.

Hint #3: No animals involved, like rodents that like to chew up wiring once they get inside vehicles parked outside.

Hint #4: No electrical soldering or wire repair of any type required to fix the problem. No electrical tape or crimp connectors used in lieu of soder either. No wiring was molested in any way.

You surely must get the answer after this. In case you do not, here are more hints that are a dead giveaway! Or are they?
OK, what are we left with?

Hint #5: No special skill required, unless you include turning a screwdriver.

Hint #6: Only tool used in repair was a T-15 Torx screwdriver.

Hint #7: No chemicals were used in the process.

Hint #8: Once problem was diagnosed, repair took approximately 1 minute! (after 1-2 hours of screwing around with other things that people on various forums and threads suggested in relation to inoperative H2 seats and heaters).

Hint #9: Pat Benetar's song, "Hit me with your best shot" was playing in the background. Kind of overall relates to my life living with Hummer repairs. Not really a hint, but ya' know. LOL!

Nucking Futs!


Wait......

Hint #10: No new parts required! Unbelievable!

And being from Vancouver, we get the same wet weather as you do in the UK. You forgot to ask about "moisture".....

 

Ok...Something some ware had come lose and required tightening..... A terminal that looked tight but had actually had no contact until tightened by Mr Torx.

Gheeeeeeeeeeeeeeeeeeeeeeeeez I won't be able to sleep tonight.​​​​​​​

 

Good guess again!

But sad to say, NO! The screwdriver was NOT used to tighten anything that had become loose. Does that help?

 

.. never actually worked on seat switch area, it looks like there are 4 Torx screws holding on the facia plate, so perhaps removing this revealed something jamming the switch travel, maybe one of the wife's hair grips, a coin or something ?

 

Well after saying that... It means that the Torx end was not used... so....Maybe you used the handle to Beat T S out of something ....sorta like a "Fonz" thing from Happy days where he gives the soda machine a wack and it starts to work.

Man am I out in left field......LMAO

 

All good guesses actually. You are creative!.
But no, the Torx end was used. Just not to tighten anything. I am just using tricky language.

 

YES, you are getting warmer! The Torx driver was used to LOOSEN the 4 Torx screws holding on the facia plate. And YES again! Removing this plate revealed the problem.
But as I mentioned before, NO foreign objects were involved. Nothing jamming the switch travel.

Maybe this all not fair, as you mentioned you have never opened up that area.

But you still did not ask me about "moisture".

When do I give away the answer?

 

corroded switch contacts...