2018 heated/cooled seat issue

mep32jep

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Hoping someone can help. I have a 2018 GT convertible with heated/cooled seats. The dash lights work but the seats will not turn on. I read where others have has issues with a module under the passenger seat. My car does not have a module there. In researching the web, I see that Lakeland Ford shows a module for the 2018 under the driver seat. I don't have one there either. All wires are connected so I can see where a module would even go. I have checked all fuses related to the seats according to the owners manual as well as the under hood relay. Any other relays to check or thoughts? Thanks for the help.

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Balr14

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It should still be under warranty. Take it to a dealer.
 
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mep32jep

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Unfortunately warranty is gone.
 

Balr14

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Did the seats ever work? I have a GT convertible too and have never used my heat/cool feature.
 
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mep32jep

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Did the seats ever work?
Not since I have had the car. I have owned it for about 2 months. Everything I read is misleading. One thing says there are relays under the drivers seat, one says there is a module under the drivers seat while another says it's under the passenger seats. My daughter's 2025 Ecoboost has the module under the passenger seat. Mine has nothing like that.
 

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If the car was equipped from the factory with heated/cooled seats, there absolutely has to be a module box at least under the passenger seat. But I think there's also one under the driver's seat, since each seat needs a heating/cooling module... but only the passenger seat reportedly has the main seat module. I need to look for those connectors too, since my car is throwing a driver's side TED-related DTC, although the cooling feature still works most of the time. But your first step is to retrieve the codes via FORScan, so you know what you're dealing with. Mine is 'resistance below threshold'. I won't take it to a dealer, especially since it keeps working, but hope it doesn't crap out completely. Will not erase the code anymore (did it twice already), since it doesn't affect anything, and now I know it wasn't a fluke. Good luck.
 
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mep32jep

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If the car was equipped from the factory with heated/cooled seats, there absolutely has to be a module box at least under the passenger seat. But I think there's also one under the driver's seat, since each seat needs a heating/cooling module... but only the passenger seat reportedly has the main seat module. I need to look for those connectors too, since my car is throwing a driver's side TED-related DTC, although the cooling feature still works most of the time. But your first step is to retrieve the codes via FORScan, so you know what you're dealing with. Mine is 'resistance below threshold'. I won't take it to a dealer, especially since it keeps working, but hope it doesn't crap out completely. Will not erase the code anymore (did it twice already), since it doesn't affect anything, and now I know it wasn't a fluke. Good luck.
No codes are being thrown and there is not another electrical harness to plug in to anything. Might be time to pull up the carpet
 

Balr14

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I looked under my seats and if there is a module it must be integrated into the seat bottom. I found nothing obvious.
 
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mep32jep

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I looked under my seats and if there is a module it must be integrated into the seat bottom. I found nothing obvious.
Thank you for looking. I think they must have changed them up in 2018 due to the issues with the previous modules burning out.
 
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mep32jep

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Here is a picture of the only module under either seat and it's under the drivers side. Numbers show that it is a Power Control Module. I wonder if the heating control is pray of this and has stopped working for.some reason. Any thoughts? Thanks

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Elp_jc

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Yeah, that's the Driver Seat Module. If equipped with cooled/heated seats, there's an extra module inside it, called the SCM-E. Then a TED/fan assembly on the seat bottom and seat back (total of 2). I was expecting the seat heating to also activate the fan, but that's not the case. So my guess is there has to be a regular heating element in both the seat cushion and seat back, just like any other car. If nothing is working (both cooling or heating functions), I'd start with the fuse. If okay, then I'd suspect the module, since it'd be extremely rare that everything crapped out at once.

Did you reset both the DSM and SCM-E modules? I'd try that too. I did, and my seat cooling works, but haven't checked if the SCM-E threw the same code again. Will probably do it tomorrow.
 
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mep32jep

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Yeah, that's the Driver Seat Module. If equipped with cooled/heated seats, there's an extra module inside it, called the SCM-E. Then a TED/fan assembly on the seat bottom and seat back (total of 2). I was expecting the seat heating to also activate the fan, but that's not the case. So my guess is there has to be a regular heating element in both the seat cushion and seat back, just like any other car. If nothing is working (both cooling or heating functions), I'd start with the fuse. If okay, then I'd suspect the module, since it'd be extremely rare that everything crapped out at once.

Did you reset both the DSM and SCM-E modules? I'd try that too. I did, and my seat cooling works, but haven't checked if the SCM-E threw the same code again. Will probably do it tomorrow.
So the module pictured does control the heating and cooling seats? How do you reset it? All fuses look good so I might try replacing that module if in fact it helps control the heating/cooling feature.
 

Elp_jc

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Yes, it controls the heat and cool functions, but as I mentioned, the other parts of the system might be bad, and not the module. Check for codes; they'd tell you what it is. In my case, I got a seatback TED code where resistance was below threshold. It still works though. I reset both the DSM and SCM-E modules via FORScan (the wrench menu). Tried both the heat and cool functions and they worked (as usual), but haven't checked if the code was thrown again. If it did, I won't erase it anymore. The weird thing is everything still works, but might crap out later, I guess. I won't use the cooling function too long again, which is probably what triggered the code (the back of the seat felt pretty hot).
 
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mep32jep

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I ordered a new module. Cost $80. Figure with all the other trouble shooting I have done,.might as well try that. I will respond back when it arrives in 5 days
 

Elp_jc

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Sounds cheap for the DSM/SCM-E one (for cooled/heated seats), but glad to hear it's that cheap. Good luck, and let us know what happened.
 

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