Just bought a hummer h2. Driver side seat warmer button is not working. Does not illuminate . Neither is the window switch that makes all 4 windows go down and up and memory seats button also not working. When I press the buttons nothing happens. No clicks or anything. Could it be a fuse? Wires?

 

If the unit is totally unresponsive i.e. nothing works then it could be a fuse, but history suggests it will a problem with the module itself. Check the 15A DDM Fuse (Left Side of Dash)

Water tends to get inside the DDM and corrodes the PCB tracks and/or switch circuitry.

Sometimes the tracks can be cleaned-up but quite often the corrosion gets under the microcontroller which is hard to fix.
Here is a little video about the DDM:-

If it's not the fuse, you might get lucky in with repairing the module yourself or it will need replacing.

 

Here is a DDM with the CPU (IC3) removed, you can see the corrosion:-


Tough to fix.

 

checked the fuse and looks good. Replaced it anyways and still nothing. All the buttons work on the switch. Power windows locks and all that work. Only the part where the memory seats and heated seats are don’t work. And mine has the button that makes all 4 windows go down at the same time that also doesn’t work. Would it still be an issue with the switch from the video? Also would the door panel need to be removed or is it like the old Silverados where you can just pop the switch out?

 

Indeed it's not the fuse as some of the module works. I'll look further on Monday.

 

Another remote possibility is that someone replaced the DDM before with the wrong one that does not have the correct programming. I found this is required on my 2003 (03/04 does not have the global windows buttons) when I added the global windows functionality. I first just got the button panel with the 2 global windows buttons but the buttons did not do anything. I have a Tech2 and looking at live data the Tech2 could "see" when I pressed those buttons but nothing actually happened. Turns out the DDM has programming specifically for that so I had to replace the DDM with one for an 05-07 one (which was not cheap). I also first tried reprogramming my 2003 one using the Tech2 and TIS2000 but the 2003 DDM would not accept the 2005+ programming (using a 2005+ VIN so that the newer programming would even show up).

So if the DDM was replaced with one from some other GM truck or SUV or from an earlier H2 then those buttons will not function. The DDM's are all physically identical but they do have different functions in their software.

Just another possibility though..... More likely that there is just water corrosion inside the DDM.

 

To add to MixManSC's comments, just to clarify, do the heated seat LEDS ever come on, i.e. even for a split second?

Typically a heater element fault causes the LEDS to blink momentarily, if they do it means there are two issues here, anyway I'll assume they don't as no doubt you would have noted it.

If you operate the heated seat switch does the driver's seat heat-up? (in case its an indicator LED circuit problem)

Do Memory Buttons 1 or 2 work?

To answer your question, the DDM can easily be removed in seconds using plastic panel levers, so there's no need to remove the door panel (you can see this at the start of the video) not sure if the Memory/Heated Switch Panel pops-out, however it looks like it should, but never actually tried it.

As your module works n every other sense, it could be a wiring issue, from the diagrams it looks like the is the Memory/Heated Switch Panel wires directly to Connector C5, the 12-Way Green connector which plugs directly into the DDM, if this was unplugged or the panel was faulty you would get the same fault.

It could be an electronic issue, there are a couple of IC's and circuitry involved. Q. the Drivers Door Ajar detection, does this work?

IC P/No BTS716 has an output that drives all of the functions of Memory/Heated Switch Panel. You can see I've highlighted the track that runs from pin 18 to C5-pin 11 if this track is broken (corroded) or the BTS716 is faulty then either could cause your issues.



Again the DDM comes apart quite easily and if you're adventurous you could check the two pcbs for corrosion and check the continuity of the highlighted track run.

Note P/Nos 84D442437R03 and 84D442437R01, I believe these are Rev3 and Rev1 pcbs respectively. Presumably there will be a Rev2 and possibly Revs 4 and 5 etc but in this case Rev3 had the Global Windows, Rev1 did not, which may be a way to confirm the software as MixManSC mentioned.

Incidentally I have repaired water corroded tracks in the past, it seems a fairly common.

Hope this info helps and please keep us posted ✔️

 

water sometimes drips onto the memory button / heater button panel from leaking door seals usually at the top corner where it rounds the A pillar to roof. you can pop off that button panel and open it to clean it sometimes they get corrosion

 

It is actually a very simple problem I have had on 2 different H2, and just fixed it on one last week.

Underseat power connector under driver seat controls ALL those functions, and then some.

It will be melted inside.
Unclip the black plastic cover starting at back seat end. Disconnect purple lock tab. Tricky. Unclip large black connector fro floorboard metal plate.
Pull apart and look inside. You may have to wiggle it quite a bit if connectors are melted together.

Once u open it with great care, look for burned up connectors on the 2 large wires going in and out of it. Kitty corner to each other. Voila!
Those are the hots. Jump them outside of the connector with insulated 12GA (yellow) crimp connector disconnects so you can still remove the seat in the future if need be.

Keep it tight and clean. That harness slides along the floor, as seat moves forward and back. U want zero snags, or it is all over.

Visit my prior post about this on this forum to see the burned up innards.
Very poor GM design using a connector not rated for this load. GM screwed this up more than they screwed up my C8 Corvette.

I have researched this, and Decided not to replace the connector for that reason.

Easy peasy if you can do electronic repairs. If not, its dealer-time.

If u need to rework connector innards and change pins, well, u just have to ask me how, there is a trick. But it is not easy if the innards are melted.

 

Afi42678 did you ever fix the issue?