Heated seat mystery

[RDayfield]

Ok, please help solve this mystery. I have an 09 Tahoe LTZ with 130 K on it. We purchased it used with 60k and the only thing that didn’t work wAs the drivers heated seat pad and back. Fast forward a few years, I ordered new seat heater pads removed the seat to install them and for the life of me I do not see that there were original seat he@ters ever in the seat. The seat has the cooling feature, and it seems to work, but there are no heat pads and no empty plugs. Why would the seat have the ac feature, power lumbar, power everything and no heat pads?
Am I missing something here?

In addition, the indicator lights light come on and stay on. There are no signs of a short, and the relay clicks when you turn it on. Also, heat and ac work on passenger seat, and both rear seat heaters work.

Please help.

 

[mikeyss]

There are no heater pads. The heat comes from a blower motor under the seat, and one is in the seat back. The A/C also comes out of those blower motors. It's called a TED (thermoelectric device) and it's a peltier type unit. The control module under the passenger seat controls both front seats and a common issue is a ground wire heats up and melts the connector.

 

[mikeyss]

My 09 LTZ has heated and cooled seats too, and in mine that wire I spoke of is Just starting to show signs of getting hot, and for some reason, my driver's seat bottom isn't heating up much... It gets warm but never hot like the seat back and passenger side do.

 

[RDayfield]

There are no heater pads. The heat comes from a blower motor under the seat, and one is in the seat back. The A/C also comes out of those blower motors. It's called a TED (thermoelectric device) and it's a peltier type unit. The control module under the passenger seat controls both front seats and a common issue is a ground wire heats up and melts the connector.

I knew it had to be something like that. Is the ground wire usually under the passenger seat?
And thank you for the response.

 

[mikeyss]

If you look under the front of the passenger seat, you'll see a gray square module. There are like 3 different plugs to it. Look for the connector with the thick wires. Unplug it if you can, if it's melted it won't come out. Sometimes you can even see the wire around the pin burnt or disformed

 

[swathdiver]

Ok, please help solve this mystery. I have an 09 Tahoe LTZ with 130 K on it. We purchased it used with 60k and the only thing that didn’t work wAs the drivers heated seat pad and back. Fast forward a few years, I ordered new seat heater pads removed the seat to install them and for the life of me I do not see that there were original seat he@ters ever in the seat. The seat has the cooling feature, and it seems to work, but there are no heat pads and no empty plugs. Why would the seat have the ac feature, power lumbar, power everything and no heat pads?
Am I missing something here?

In addition, the indicator lights light come on and stay on. There are no signs of a short, and the relay clicks when you turn it on. Also, heat and ac work on passenger seat, and both rear seat heaters work.

Please help.

Do you have diagrams to compare with what you're looking at? Can you post up some photos for us? I reckon it's possible that during manufacture they forgot to put the elements in the padding. I'd also like to see a scan of the BCM if it were mine.

 

[mikeyss]

I will post some pictures I found later on. But the seats that have cooled function do not have heating elements in the foam. The blower under the seat and blower in the seat back do both, either cool or heat. The seats that are heat only will have heating elements in the foam. You can use a tech2 to command them on or off when diagnosing them too.

 

[mikeyss]

https://www.ebay.com/p/OEM-Front-Se...Avalanche-Yukon-Escalade-25789849/25017005749