99 Suburban heated seat

[chuck's]

In a previous post I mentioned about the heated seat switch and the seat belt buckle switch.From my experience,if either one does not work,then the "click" sound within the module will not work.My lower seat cushion elements do not work,but my module does "click".Other than that, if you can check for power to the lower element from the module,that would be my next check.I hope this helps you along.
chuck's

[cris2004]

Thanks, Chuck's.
I guess I'm having trouble being certain the seat belt switch and/or control switch functions properly. I cant seem to identify what the working side does differently than the other!
I lamp tested the working side, at the modual, and got orange -hot always, and the pink stripe -hot only when the unit is set to med or high. The non working side functions the same.
My belt warning does work normally. My Chiltons and Haynes both fail to show a diagram on the seats.

Do any of theses wires go to ground to function? I have tried to get lamps to light on the other working side wires without success.
Thanks again.

[chuck's]

Check for a voltage at pin B of the module with the switch on,seatbelt buckled and ignition on.There should be two voltages,one greater than the other.(hi or low position)If no signal there.I believe the relay in the module will not energize.As you stated,the pink with black stripe wire should have power when the swicth is turned on.Power to the elements come from pin A on the module.I hope this will help.
chuck's

[cris2004]

Thanks again for the help.
I do get voltage at B, but do not at A. Incidently, I get volts at B even w/o the belt buckled, if that means anything.

What is the source of "A" 's voltage? The switch seems to function as indicated by the b volts, and I do not get voltage on 'A' on either side.even on the side that does funtion normally.

Thanks

[chuck's]

If the module is working on the good side,there has to be a voltage at pin A because the elements get their power from this pin.It could be possible that the seat temperature sensor is inoperable.I think that if the module does not get a signal at pin E the module may not energize.As the seats heat up.the sensor controls when the the module comes on or off.Using an ohm meter check for continuity of the sensor.Four pin connector with the black/red wire at pins C and D.I have run out of suggestions to help you.I hope this will fix your problem once and for all.
chuck's

[cris2004]

Much Appreciated. I may have to use a more sensitive meter and be more diligent to detect the pulses. I'm going to continue to compare sides till I get a discrepancy, may be put jumpers wire between the mod and its connector on the good side and remove them one at a time till I match the non working side, then trace the source. Thanks for the help. it may be a couple weeks before I get back to it.

Chris

[bigmar54]

Hello,
i have a 99 K1500 5.7 and my passenger side heated seat went out along with the little light on the window button on the passenger side door about the same time,could this possible be wiring related issues.
Thanks

[Master Brian]

Is anyone still following this and/or has there been anything figured out?

I have a 99 Suburban as well and the driver side heated seat doesn't work. I found that the top cover/element ohms out as completing the circuit, but I can't get the bottom cover/element to ohm out. I compared it to the passanger side and have different readings.

I have an aftermarket element that I was going to install but upon tearing the cover off, I decided it wouldn't work because GM used velcro to hold the tucked areas down and the aftermarket called for holes to be cut a max of 1" and to use hog ring staples.

Has anyone used an aftermarket pad on these or know of a good way to "fix" the element? it seems to be "built-into" the cushion.

BTW...from what I could gather the top element will only work if the bottom element works. It appears that the module is energizing as I hear noise from it when I turn the seat on. With this and considering the bottom element doesn't ohm out, I'm assuming that is where my issue lies.

One more thing for others, checking the resistence of the element is easy to do and you don't even need to pull the seat, you just have to access the harness for the top or bottom seat cushion. The plug for the top pad is just under the area where the cover "zips" together and contains a black and purple wire. The plug for the bottom pad is in the center rear underside of the seat, it is a 4 prong plug with 2 yellows and two blacks. Judgeing from my passenger seat the yellows should ohm across, I got a reading of 15 or so on the black wires. Not sure what that was....

[chuck's]

Yes, it would be nice to have the heated seats to work.I investigated my seat problem only to find that I had a module and seat element nonfuntional.Without looking into aftermarket elements,I just put a jumper wire into the four prong connector to get the upper element to work.The draw back from doing this is that the temperature control switch is also bypassed.Good luck with your challenge.

chuck's

[Master Brian]

Originally Posted by chuck's

Yes, it would be nice to have the heated seats to work.I investigated my seat problem only to find that I had a module and seat element nonfuntional.Without looking into aftermarket elements,I just put a jumper wire into the four prong connector to get the upper element to work.The draw back from doing this is that the temperature control switch is also bypassed.Good luck with your challenge.

chuck's

Did you jump all 4 wires on the 4 pin harness or just the two that go to the element? Like I believe I mentioned, I have 2 yellow and 2 black wires. I think the yellow went to the element and the black were probably the temp sensor.

Thanks for the reply,
Brian

[chuck's]

I can't remember it all,but if you have a wiring schematic it will help with my explanation.Basicly the power goes to the lower element,then up to the upper element.I would take the lead that feeds the lower element and back probe the pin to allow me to put the power to the upper element.The four pin connector is marked A B C D.I believe I placed the jumper from pin A to pin B.This bypasses the lower element and puts power to the upper element.Remember that there will be no seat temperature switch.I hope this explains better.

Chuck's

[Master Brian]

I don't have a diagram, but I can probably figure out which lead feeds the upper. I believe it is the wires that are yellow on my 4pin plug, the same wires that seem to have a short/open. I will see if I can find the letters A B C & D.

You don't have to respond if my next question is correct, but without the seat temp switch, the seat will just continue to heat up until you turn it off correct? Meaning, I would have manually turn it off, when/if it gets to hot. I would also assume, that could pose a fire hazard, if left on too long, but being as it is the driver seat and obviously someone would always be in this seat when the vehicle is running, that danger should be very low.

Thanks again for your help....

[chuck's]

Yes ,you are correct about the temperature switch.The letters A B C D will be on the outer shell of the connector.They will most likely be small and hard to see.
chuck's

[pikappkaz]

Well, I've been dealing with no heated drivers seat for a couple of years now, and I finally decided to tackle the issue this week. I was able to come across a wiring diagram (PM if you'd like it) and I did some testing with the seat out of the truck.

What I found was an open circuit in the lower (butt) heating element. Like it was stated earlier, the circuit for the element is the two yellow wires in the 4 wire plug (I'd have to double check to see the right letters on them).

I decided to pull apart the seat, because that's what engineers do. This was much easier of a process than I thought, just clip the hog-rings and the seat cover comes off without any effort.

What I found was a nice burn in the foam of the seat cover, which is exactly where the broken wire was found. After taking a quick look at it, it was just a simple wire jumper that was pinched apart by the seam of the seat. This jumper connected the two small blue heating element wires that keep my butt warm. I simply peeled back the foam, cleaned up the part that pinched the wire apart, and soldered a nice new jumper wire into the mix. After some research online, I used a 14AWG, primary wire from the auto store, most of us have a piece or two lying around (3" is all it took). I couldn't find hog-rings or pliers for the life of me, so I just used some sturdy tie-wraps to put the seat back together, time will tell on that issue.

Took a test drive and my rear end was very happy, as well as my wallet. This repair cost $0, and fixed a problem that was around for way too long. It really didn't take any special tools, and it also didn't require a whole lot of muscle.

Let me know if you have any questions about the repair, I'd be happy to give some advice.

[Master Brian]

Originally Posted by pikappkaz

Well, I've been dealing with no heated drivers seat for a couple of years now, and I finally decided to tackle the issue this week. I was able to come across a wiring diagram (PM if you'd like it) and I did some testing with the seat out of the truck.

What I found was an open circuit in the lower (butt) heating element. Like it was stated earlier, the circuit for the element is the two yellow wires in the 4 wire plug (I'd have to double check to see the right letters on them).

I decided to pull apart the seat, because that's what engineers do. This was much easier of a process than I thought, just clip the hog-rings and the seat cover comes off without any effort.

What I found was a nice burn in the foam of the seat cover, which is exactly where the broken wire was found. After taking a quick look at it, it was just a simple wire jumper that was pinched apart by the seam of the seat. This jumper connected the two small blue heating element wires that keep my butt warm. I simply peeled back the foam, cleaned up the part that pinched the wire apart, and soldered a nice new jumper wire into the mix. After some research online, I used a 14AWG, primary wire from the auto store, most of us have a piece or two lying around (3" is all it took). I couldn't find hog-rings or pliers for the life of me, so I just used some sturdy tie-wraps to put the seat back together, time will tell on that issue.

Took a test drive and my rear end was very happy, as well as my wallet. This repair cost $0, and fixed a problem that was around for way too long. It really didn't take any special tools, and it also didn't require a whole lot of muscle.

Let me know if you have any questions about the repair, I'd be happy to give some advice.

I would love to have a copy of that diagram if you can send it to me at [email protected]. I do appreciate it.

As far as the short, maybe I'll tear my seat back apart and see if I can find something like that. Can you tell me where exactly on your seat this happend? I don't recall any burnt looking spots, but I would bet it would be close to where your problem is, considering this seems to be a popular issue.

Also, what did you use to cover the solder connection? Can you put some heat shrink over that or is something else better?

Thanks again.