Hello,

I hope I’m posting this in the right place. I’ve done a ton of research and troubleshooting on this issue and I am officially at a loss of where to go to next.

The back part of my driver’s heated seat is not working. I replaced the element as a first step, since I had 14V at the connector going to the back element. That didn’t fix it. I connected the old element to the passenger seat and it works, so the element turned out to be good.

When measuring voltage at the connector on the passenger seat (which works) I’m getting around 5V under load, when the seat is on all the way. When I did this same test on the drivers seat the connector was only pulling about 1V with both the new element and the old element. This leads me to believe there’s a module somewhere that’s incorrectly regulating the voltage going to the back of the seat (the bottom cushion still gets hot).

I’ve found a ton of threads about the module that has a grounding issue, but this module is not present anywhere underneath either driver or passenger seat. I’ve glanced under the dash for a module similar to the one I’ve seen but haven’t been able to find it.

My truck has heated and cooled seats. The cooled portion of both seats work fine.

Thanks in advanced for any help or advice anybody can offer!

-Sam

 

The heated/cooled seats should be regulated by the DSM (driver seat module) 2018 and up. This is under, obviously, the driver's seat. It should have 5 connectors on the front side of it 3 black 1 gray and 1 brown I'm pretty sure, I'd make sure they are all plugged in fully and no wire is broken. If you have Forscan you could check for any dtcs in the DSM and I believe it still shows up as the SCME for the climate controlled seats.

It is interesting that the cushion works fine because the backrest is fed from the cushion and then it gets ground through on 2 on the backrest for both heaters.

 

Thanks for your reply! I though that module might have something to do with it but couldn’t find anything online to confirm that suspicion until your comment. I don’t have forscan (yet, it’s on order) but I took the seat out of my truck to investigate all of the wiring and from what I can tell everything looks good.

I opened up the module and I don’t see any obvious signs of a problem (no burns, missing pieces, etc) but I’ll attach some pictures.

At this point would it be worth buying a new DSM? Seems like I can get one for $150, which isn’t too bad if it fixes the issue.

Thanks again for the assistance.

 

I wouldn't buy a new module until a FORScan check for DTCs.

 

I agree, the module may be just fine and maybe it can help point you in the right direction with a dtc

 

Unfortunately, FORScan didn't find any DTCs. I'm a little disappointed since it seems I'm back at a dead end for troubleshooting this issue.

Anyone else run into this issue?

Thanks

 

Did you ever figure out the issue? I am in the same boat as you!!! Help!!!!???

 

I did. I ended up purchasing a brand new module and it fixed the issue. Here's a link to the module: https://www.ebay.com/itm/29461369977...2Cchnl%3Dmkcid

 

I hope I get that lucky as well!! Will be purchasing one!

 

OP comes through with an update/fix!

Surprised it was the module with no evidence of damage and no DTCs.