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Hi everyone! My 2004 Tahoe's overhead light that is supposed to come on when the door opens, rarely does so. Older vehicles, had an actuator that you could see and push in/out to turn off overhead light. I do not see one on my Tahoe and assume this is my issue; Does anyone know where and how the drivers side door actuator is? I assume somewhere in the door...
 

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I have a 2013 GMC Acadia and the driver's side memory buttons, driver's side seat positioning controls (all except for the lumbar support), both drivers side and passenger side heated seats (not even the lights), AND (although it may not be related) the rear DVD screen all do not work. The MSM is blown and when replaced it continues to blow. I've disconnected every cable that I could find under both seats and the cables running from the car body to the drivers side door and the fuse still blows immediately when inserted. The passenger side seat positioning works fine but there are is no memory buttons on that side. Any other ideas?
 

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The driver's door switches are very vulnerable to water. That door is the one most often opened in the rain. Try unplugging the switches. Fuses that blow immediately are usually caused by short circuits not opens. The wiring bundle from the body to the door is prone to opens. The wire breaks inside the insulation where it can't be seen.

The wiring under the seat can get crushed in the seat tracks. I think the Memory Seat Module is under the driver's seat but I'm not certain.

Ted
 

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OK so it sounds like everything runs through the power control module. My seat won't move up or down on the rear power seat. Sounds like the motor is trying to work but just buzzes. The forward up down and back and forth work just fine.

The heated seats turn off after a minute or so. Thought it was a bad heater element. Is it possible that the seat sensor is detecting that the seat isn't where it should be and killing the heaters?

Also anyone know how to fix the stuck power seat?
 

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Hey everyone, thanks for this great informative thread. I have a 2003 yukon Denali and I am having issues with the seat heating on the drivers seat only. The passenger works fine. The seat adjustment works fine as well as the brake adjustment. When I press the heat button, either the back or bottom, they click off immediately. I have been playing around with different settings and I found that if I have the seat adjustment for the back middle section pushing all the way out ( a bit uncomfortable) , then the heat actually works and stays on for both the back and bottom. Not sure why, maybe the back heater has a Cracked wire and pushing the middle adjustment all the way out creates a connection again? Its very odd, sorry if I don't make sense as I'm not good at terminology.
 

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Please excuse my tardiness, clubbers. A brake job intervened since stopping is rather more critical than a warm ...seat, and the brake job became more complicated because it involved parking brake repairs which entailed pulling the axle hubs (q.v.). And as advent turns to Christmas there have been social and family responsibilities.

But just as God will keep his advent promise of the second coming, I'm keeping my promise to share the Rest of the Story (tm) with pics.

Let's begin with some orientation. Here's the driver's side seat in my burb:

View attachment 47217

The repair begins by removing the seat bottom, which is simply a matter of removing two nuts at the front corners, undoing all the connectors, and pulling the seat up and forward to release the blind keyhole fasteners at the rear of the seat bottom. Two of the connectors are visible from the front of the seat, looking back from the area of the brake pedal:


View attachment 47218

You may find that you can disconnect them in place. I ended up prying them down from their attachment to the frame, which works too, and allows more ready access to the latch that allows them to be disconnected.

One connector is readily visible from the rear of the seat, the large connector at bottom center in this photo:
View attachment 47219

The rest are probably most easily disconnected after the seat bottom is partially removed. Once it's out, here what you'll see. The seat bottom, upside down and on the garage floor:

View attachment 47216
And the seat frame, as viewed from the headliner:

View attachment 47215

- - - Updated - - -

The seat back doesn't have to be removed. All we have to do is work the pad out of it. The first step is to open the Z-fastener at the bottom of the seat back, which attaches the front of the upholstery to the rear of the upholstery. You want to pry it apart at one end then the whole thing comes undone like a zipper. I found that an offset flat blade screwdriver made the job easiest. We're looking down along the seatback here:

View attachment 47221

It's hard to show much but the upholstery is fastened to the cushion with a couple of rows of velcro, and the heating pad is attached with a couple of adhesive strips, and kept in place by velcro that surrounds it. All you have to do is reach up with your fingers and work everything apart. Here's a photo showing some of the velcro on the cushion, from the steering wheel looking back:

View attachment 47223

Once you work everything apart and undo the connectors you will have the heating pad out.

The Dorman replacement pad comes with terrible instructions -- don't follow them, they tell you to remove the whole seat assembly from the truck, which is a major undertaking and which will not help matters. They also come with a set of hog rings and hog rungs pliers that are, apparently, useful for some other application, since they're of no use here.

Here are the pads side by side, old and new:

View attachment 47222

The Dorman pad comes fully connectorized but there's a tiedown you'll want to move from the old wiring to the new:

View attachment 47220

The other difference is that the adhesive on the Dorman pad faces towards the upholstery rather than towards the cushion. Since it appears that the velcro does most of the job of holding the pad in place, I don't think this is an important difference.

The OEM pad is constructed with a woven conductive polymer grid in a diamond shape. At the top and bottom there are about five rows of metallic wires going across the width of the pad. There are burn marks at one part of the pad where the wires weren't making contact:

View attachment 47224

Putting everything back together, the important thing is to get all the wires dressed in so they won't chafe. The three connectors at the rear inboard corner of the seat have to be connected before assembly. The others can still be reached after the seat bottom is installed.

I checked the operation of all the power seat movements before starting the engine and confirming that the seats heat properly.

A final note of caution: there is a bright yellow connector below the seat that is the circuit for the airbag mounted in the seatback. It should not be disturbed.
I just learned a lot! Thanks, and not so much about the seats, I just skimmed at this point,(though interested, also very tired) but how to do a write up...and some other things too...anyway, thanks.
 

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Hey I have a 2006 silverado crew cab truck. No heated seats work or light up at all. Also the memory buttons don't work either. All power controls on both seats work but none of the door buttons on either side work. Any pointers?
 

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I have a 2004 Suburban. Passenger heated seats work but driver seat comes on for 3 seconds and shuts off with a click noise under dash. If a push the button again the heated seat light justs blips for a micro second. I then found out if I move any seat control then the driver seat comes on for 3 seconds and shuts off again I can keep repeating this with different seat controls but if I stop moving any seat control then it goes right back to shutting off in a micro second. Neither of the drivers top or bottom heated part will stay on by itself. Any ideas for this situation?
 

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I have a 2004 Suburban. Passenger heated seats work but driver seat comes on for 3 seconds and shuts off with a click noise under dash. If a push the button again the heated seat light justs blips for a micro second. I then found out if I move any seat control then the driver seat comes on for 3 seconds and shuts off again I can keep repeating this with different seat controls but if I stop moving any seat control then it goes right back to shutting off in a micro second. Neither of the drivers top or bottom heated part will stay on by itself. Any ideas for this situation?
ImI literally experiexperiethe exact same issue with the seat heater/memory/ driver selector keeps turning on/off randomly and won't stop. Also having issue with my battery being dead ao imI'starting to wonder if this is happening while the tahoe is locked
 

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I have a 2004 Suburban. Passenger heated seats work but driver seat comes on for 3 seconds and shuts off with a click noise under dash. If a push the button again the heated seat light justs blips for a micro second. I then found out if I move any seat control then the driver seat comes on for 3 seconds and shuts off again I can keep repeating this with different seat controls but if I stop moving any seat control then it goes right back to shutting off in a micro second. Neither of the drivers top or bottom heated part will stay on by itself. Any ideas for this situation?
Hey Jimmy John, I'm having the exact same issue with my Yukon Denali. Did you ever get your issue fixed? I would sure like to know what's going on
 

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This applies to everything built on the full-size GMT800 truck platform -- Silverado, Sierra, Suburban, Yukon, Escalade, Tahoe.

The seat system on these trucks is complex and is not covered in depth in the Hayes book or anywhere else on teh internets so here is the GM Truck Club exxclusive writeup. I will add some photos another day.

I'll explain basic troubleshooting steps, common problems, and repair methods with the heated seats, which fail frequently. Much of the same info applies to problems with the power seat adjuster.

Before you complain tl;dr well these things are complicated and so I'm going to have to use a lot of words to explain it so hold on and pay attention, you want simple either get a 1997 or complain to The General.

== System design ==

There's microcontroller module under the driver's seat that runs the whole show. The General calls this the "memory seat module." It connects to a wiring harness in the rails under the seat using four large multi-pin connectors. This wiring harness, in turn, has connections to each of three seat motors, the chassis, the seat bottom, and the seat back.

There's just one "memory seat module" controlling both seats, and also controlling the adjustable brake and accelerator pedals.

The control switches for the heated seats in each door don't have a physical circuit to the "memory seat module" but rather communicate using the chassis serial bus.

The reason we didn't really see heated seats very often before the late 1990s is that they tend to fail in ways that cause them to overheat and start the seat foam on fire. To deal with this the microcontroller in the "memory seat module" provides close supervision of the whole system, with a temperature sensor in each seat, and sensing of the current draw for each of the four elements. If the microcontroller detects anything dodgy going on it shuts down the whole heated seat subsystem until the next time the ignition is switched off and on.

There are nine sensors in this system. Each seat has three position sensors and one temperature sensor, and then there's a sensor for the position of the accelerator/brake pedals.

These sensors all share a 5 volt supply from the "memory seat module." As a result, if any of them short to ground, the "memory seat module" can't sense temperature or seat position and pretty much shuts down everything.

== Common failures ==

The flexible heater pads fail most often. The temperature sensor is incorporated into the seat back heating pad, and the whole thing with connectors is serviced as an assembly. The seat bottom heating pad doesn't have a sensor. Dorman makes both these so you can get them from NAPA, Carquest, Rock Auto, etc., for around $100 each. They're a fast moving part and my local NAPA had them in stock.

Next most common is a wiring short to ground, most commonly in the wire bundle that goes up to the seat back assembly next to the seat belt latch. That's an easy fix with some tape and a little piece of wire loom. Otherwise well yes you can have a wiring short pretty much anywhere under either seat because the seats move and the wires flex, and if they're not dressed quite right they will rub.

Next up we have the power wiring to the drivers side seat. Well when you hit the memory button there's the possibility of all 7 motors running at once and so that's quite a current draw, more than for the heated seats, and it's common for the connector between teh chassis wiring and the seat frame to overheat. Now this connector has maybe 24 circuits going through it but you can just cut the power and ground wire and crimp on some bullet or spade connectors on those and call it good.

Finally though rare the position sensor for the accelerator/brake pedal assembly can short out and since it shares the same +5 volt power supply with everything else the whole thing quits working.

== Troubleshooting ==

If you are a tech at a stealership then The General gives you access to DTCs in the "memory seat module" that are supposed to help. The rest of us have to go lo-tech.

If nothing on either seat works at all, no movement, no heat, nothing -- either intermittently or all the time -- undo the grey connector near the floor under the driver's seat. On anything with a second row of seats you can get at it fairly easily from the second row, on a regular cab pickup you'll have a time of it. Look at the connector pins for signs of overheating on the orange and black wires, if so, cut those two wires and crimp on a suitable bullet or spade connector. They are hot with the key off so either be careful or disconnect the battery ground strap.

For heated seat problems the first thing to do is determine if one side or both sides are affected. The engine has to be running for the heated seats to work so start things up and check one side. See if you can turn on the seat heat, and then see whether it will stay on for at least a minute or so. Then turn the key all the way off to reset the "memory seat module," want a few seconds, fire it back up, and check the other side. Once the "memory seat module" has identified a fault in either seat it shuts them both down so you have to do this or you'll fool yourself into thinking they're both broken.

If one side works OK but the other side doesn't do anything at all, the lights don't flash even a little, or one button works when you mash it but the other one doesn't, then the switch module in the door panel is probably toast.

If one side works OK but on the other side the lights come on and then shut off either right away or after a few seconds or half a minute or whatever then chances are that you just need to replace the heating pad on the bad side. You can isolate whether it's the back or the bottom pad by shutting off the engine again, starting it up, and mashing the "back heat only" button on the bad side. If that works OK and stays on for a minute or more well then the problem is with the bottom pad, on the other hand if it shuts off on "back heat only" then it's the back pad that you have to replace.

If both sides are bad try moving the seats using the power seat controls. If the seats just move in fits and starts well then you have shorted sensor wiring somewhere. You can crawl under the dash and disconnect the connector to the brake/accelerator pedal position sensor, which is up above the brake pedal. If you hold the brake pedal down and look up there you can see it moving on the pedal assembly. Just pop the connector out. Now that you've done that you can fire up the engine and see if that fixed anything, if it did well you need a new pedal position sensor from your local stealership.

Otherwise there's a short somewhere else and you're going to have to take the seat bottoms out and look for wires rubbed off. The wire going to the seat back, near the seatbelt latch, is a known problem area, but the short could be anywhere. You remove the seat bottoms by undoing the two nuts underneath at the front of the seat, and the disconnecting *all* the connectors. It took me a half hour to figure out how to pop them all loose because they're all different. I'm not going to try to describe it so just take a deep breath, get your flashlight and a little screwdriver, and start fussing. I would suggest disconnecting the battery ground strap before you start so one of the seat motors doesn't fire up at the wrong time and squish your fingerz.

The power seat module itself can fail but that's rare and expensive to fix. The stealership has to flash it for your specific situation so there's no guarantee that a boneyard one will work. There were some flash updates that came out ages ago to fix a problem with the heated seats shutting down for no good reason -- apparently the original software was a little too paranoid -- but most vehicles will already have those applied.

Well if you try all that and still can't get the seats to work you probably should just trade in your truck because chances are at that point even if you take it to the stealership they'll charge you $500 for half a day of diagnostics and won't be able to figure it out either.

Photos to follow tomorrow
I have a 2010 avalanche LTZ
Seat heater/cooling/adjusting buttons don’t even light up indicating no power???
 

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Please excuse my tardiness, clubbers. A brake job intervened since stopping is rather more critical than a warm ...seat, and the brake job became more complicated because it involved parking brake repairs which entailed pulling the axle hubs (q.v.). And as advent turns to Christmas there have been social and family responsibilities.

But just as God will keep his advent promise of the second coming, I'm keeping my promise to share the Rest of the Story (tm) with pics.

Let's begin with some orientation. Here's the driver's side seat in my burb:

View attachment 47217

The repair begins by removing the seat bottom, which is simply a matter of removing two nuts at the front corners, undoing all the connectors, and pulling the seat up and forward to release the blind keyhole fasteners at the rear of the seat bottom. Two of the connectors are visible from the front of the seat, looking back from the area of the brake pedal:


View attachment 47218

You may find that you can disconnect them in place. I ended up prying them down from their attachment to the frame, which works too, and allows more ready access to the latch that allows them to be disconnected.

One connector is readily visible from the rear of the seat, the large connector at bottom center in this photo:
View attachment 47219

The rest are probably most easily disconnected after the seat bottom is partially removed. Once it's out, here what you'll see. The seat bottom, upside down and on the garage floor:

View attachment 47216
And the seat frame, as viewed from the headliner:

View attachment 47215

- - - Updated - - -

The seat back doesn't have to be removed. All we have to do is work the pad out of it. The first step is to open the Z-fastener at the bottom of the seat back, which attaches the front of the upholstery to the rear of the upholstery. You want to pry it apart at one end then the whole thing comes undone like a zipper. I found that an offset flat blade screwdriver made the job easiest. We're looking down along the seatback here:

View attachment 47221

It's hard to show much but the upholstery is fastened to the cushion with a couple of rows of velcro, and the heating pad is attached with a couple of adhesive strips, and kept in place by velcro that surrounds it. All you have to do is reach up with your fingers and work everything apart. Here's a photo showing some of the velcro on the cushion, from the steering wheel looking back:

View attachment 47223

Once you work everything apart and undo the connectors you will have the heating pad out.

The Dorman replacement pad comes with terrible instructions -- don't follow them, they tell you to remove the whole seat assembly from the truck, which is a major undertaking and which will not help matters. They also come with a set of hog rings and hog rungs pliers that are, apparently, useful for some other application, since they're of no use here.

Here are the pads side by side, old and new:

View attachment 47222

The Dorman pad comes fully connectorized but there's a tiedown you'll want to move from the old wiring to the new:

View attachment 47220

The other difference is that the adhesive on the Dorman pad faces towards the upholstery rather than towards the cushion. Since it appears that the velcro does most of the job of holding the pad in place, I don't think this is an important difference.

The OEM pad is constructed with a woven conductive polymer grid in a diamond shape. At the top and bottom there are about five rows of metallic wires going across the width of the pad. There are burn marks at one part of the pad where the wires weren't making contact:

View attachment 47224

Putting everything back together, the important thing is to get all the wires dressed in so they won't chafe. The three connectors at the rear inboard corner of the seat have to be connected before assembly. The others can still be reached after the seat bottom is installed.

I checked the operation of all the power seat movements before starting the engine and confirming that the seats heat properly.

A final note of caution: there is a bright yellow connector below the seat that is the circuit for the airbag mounted in the seatback. It should not be disturbed.
GMTruckClub
Very good information and learning a lot about an issue I am trying to troubleshoot on my 06 Hummer. Fortunately there is this club which has very similar components to my Hummer. Unfortunately it looks like all of us have similar headaches. My issue is the driver seat power functions do not work however do respond to the memory buttons and when driven with a Snap-On computer. Also the seat heaters on both seats work intermittently. Dealer said I have a bad power seat module but not sure I am fully on board. Can the module be bad if the seat can be adjusted with the computer? I just want to confirm this is the issue before I run around trying to find a discontinued part.
 

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This is an old post BUT - my 03 I had the classic heater pad wear through. I replaced both upper and lower (APDTY product) and only the lower heats (passenger side heats fine). I swapped out the new lower for another new one (Dorman) and only the back heats. I pulled both new ones and replaced with two new Dormans - only the back heats. I replaced the upper and lower pads with "The Seat Shop" pads - only the back heats. I swapped out the seat heater switch on the door panel with a parts car, same issue only the back works. I unplugged the adjustable pedals connector from the unit at the brake pedal - still only the back heats. There are NO visible shorts and the switch stays on just heating the back. I'm a little pissed off at this point as you could imagine, its at the peak of cold in Ohio and I have a short enough drive that its miserable because the truck barely heats up by the time I get to work (the seat heater would be much enjoyed). Any thoughts?
 

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I know this is an old post. However, I just stumbled upon it. My issue is my 2011 Tahoe heated seats. Using the remote start, the driver's seat does not turn on, the passenger side turns on. Both seats work fine manually. I noticed the lights would go out on the driver's door when I closed it. I replaced the switch, and now the driver seat works intermittently using remote start. Puzzled where to start looking, and what to test.
 
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