Heated seats not heating

[Majestic]

I've searched and see where others have had this issue. I have not been able to locate the solution.

I turn on the seat heaters on the screen, lights illuminate and the fans under the seat come on. However, no heat is coming out. I checked the filters and they are clean.

 

[Majestic]

I have verified that none of the seats, front or rear, have heat despite the lights/fans operating. Is there a valve that could be blocked?

 

[yaycandy]

Check fuse 28 under the hood. 30 amper. Sometimes just pulling it out and putting back in fixes the issue. Happened to me a couple times. And hopefully its not your module, ill check tasca for pricing just incase.

https://www.tascaparts.com/oem-parts/ford-seat-heater-control-module-bu5z14c724a

I kinda doubt its a module, because then it would be all of them bad at the same time

 

[Johnbigdog]

Our cars use a device called. T.E.D. (Thermal Electric Device) that heats or cools the air and a blower is used to blow air across that T.E.D. to heat your posterior and back. It typically takes 10 mineuts to heat up if it's cold outside. The TED can add about 100 degrees F. To the ambient air.

If you are hearing the fans working, the teds are working, but it is posibel the duct work is damaged preventing the heated air getting through the seats.

 

[Majestic]

Our cars use a device called. T.E.D. (Thermal Electric Device) that heats or cools the air and a blower is used to blow air across that T.E.D. to heat your posterior and back. It typically takes 10 mineuts to heat up if it's cold outside. The TED can add about 100 degrees F. To the ambient air.

If you are hearing the fans working, the teds are working, but it is posibel the duct work is damaged preventing the heated air getting through the seats.

Do you have a diagram of the duct layout? I can't imagine how it could be damaged/blocked, but that seems most likely to me.

 

[Johnbigdog]

Do you have a diagram of the duct layout? I can't imagine how it could be damaged/blocked, but that seems most likely to me.

No. There is one ted/blower per cushion seat back. It blows into the cushion and cover.

 

[Majestic]

No. There is one ted/blower per cushion seat back. It blows into the cushion and cover.

Forgive me if I'm being obtuse. I already stated that the fans are working. You posted, "If you are hearing the fans working, the teds are working, but it is posibel the duct work is damaged preventing the heated air getting through the seats."

Then I asked if you had a diagram for the duct layout, to which you responded, "No. There is one ted/blower per cushion seat back. It blows into the cushion and cover."

So.... you don't have the layout I referenced, or there is no duct layout because senor Ted handles everything?

Again, sorry if I'm coming across as stoopid. Just trying to figure out where to start.

 

[Johnbigdog]

Forgive me if I'm being obtuse. I already stated that the fans are working. You posted, "If you are hearing the fans working, the teds are working, but it is posibel the duct work is damaged preventing the heated air getting through the seats."

Then I asked if you had a diagram for the duct layout, to which you responded, "No. There is one ted/blower per cushion seat back. It blows into the cushion and cover."

So.... you don't have the layout I referenced, or there is no duct layout because senor Ted handles everything?

Again, sorry if I'm coming across as stoopid. Just trying to figure out where to start.

No its ok. Its been a long day and I'm tired so my explanations are crap.

There isn't a layout diagram for anything for the climate controlled seats.

If you remove both seats you can see the cushion teds to see if they are damaged or not seated against the cushion well.

When you are looking at the teds there is an exhaust side that air will blow out of that is normal. There is another side that blows up and into the cushion. You can pull the ted away and make sure that it blows warm air out the side that fits into the cushion or backrest. I forget how the seat back cover comes off to get to the seat backrest TED.

The dual climate control seat module that controls everything is under the passenger seat. You can make sure the connectors are not burnt.

The next step would be to either monitor pid data for the thermistors built into the teds to see if they are biased. You could also ohm them out with a ohm meter.

 

[Majestic]

No its ok. Its been a long day and I'm tired so my explanations are crap.

There isn't a layout diagram for anything for the climate controlled seats.

If you remove both seats you can see the cushion teds to see if they are damaged or not seated against the cushion well.

When you are looking at the teds there is an exhaust side that air will blow out of that is normal. There is another side that blows up and into the cushion. You can pull the ted away and make sure that it blows warm air out the side that fits into the cushion or backrest. I forget how the seat back cover comes off to get to the seat backrest TED.

The dual climate control seat module that controls everything is under the passenger seat. You can make sure the connectors are not burnt.

The next step would be to either monitor pid data for the thermistors built into the teds to see if they are biased. You could also ohm them out with a ohm meter.

Thanks, man. I'll probably start by reading things in Forscan to see if anything shows up. Then I will look at the module under the driver's seat. I like to go for the easiest things first. I've been driving for over 30 years so, if it's a giant pain/expense to fix, well, I can live without a heated seat. My first car had manual locks and windows, no a/c and a radio with one speaker in the dash. I miss that car sometimes.

 

[Johnbigdog]

Thanks, man. I'll probably start by reading things in Forscan to see if anything shows up. Then I will look at the module under the driver's seat. I like to go for the easiest things first. I've been driving for over 30 years so, if it's a giant pain/expense to fix, well, I can live without a heated seat. My first car had manual locks and windows, no a/c and a radio with one speaker in the dash. I miss that car sometimes.

I like the technology in newer cars. Lots of fun stuff and some of it is great safety stuffs. But as more and more of it comes common place it gets harder and harder to D.I.Y.

Shit, I have acess to tools and publications and I will strait up tell you I dont understand it all and some shit don't make ANY sense to me. But I try my best that I can.

Simple is nice, but there are some creature comforts for a daily that are nice.

On that note, I own a 74 super beetle. (With no heat as is) That is about as electronically simple as it gets. I would NOT like to drive it as a daily.

 

[FiveLeeter918]

This thread reminds me that I need to investigate mine. I've need to check body codes again, I had a screenshot somewhere of my codes but can't seem to figure out how to translate them lol. need to find a decoder for the body control module.

 

[Johnbigdog]

This thread reminds me that I need to investigate mine. I've need to check body codes again, I had a screenshot somewhere of my codes but can't seem to figure out how to translate them lol. need to find a decoder for the body control module.

If you can pull the codes, shoot me a message and I'll give you the description and fault trigger condition.

 

[Majestic]

Just noticed that the lights are still coming on, but the fans under the seat will run for about a minute and then shut off. I'm thinking that switch under the seat might be the culprit. Is it difficult to get to without removing the seat?

 

[Johnbigdog]

Just noticed that the lights are still coming on, but the fans under the seat will run for about a minute and then shut off. I'm thinking that switch under the seat might be the culprit. Is it difficult to get to without removing the seat?

The button on the touch screen is just a communicated message to the module under the passenger seat.

Becuase there is a module running the climate controlled seats i bet there is a dtc setting in the module. That module is seeing a fault and tuning off the system. The click you are hearing are relays switching in the module. There isn't a replaceable switch per say.

 

[Majestic]

The button on the touch screen is just a communicated message to the module under the passenger seat.

Becuase there is a module running the climate controlled seats i bet there is a dtc setting in the module. That module is seeing a fault and tuning off the system. The click you are hearing are relays switching in the module. There isn't a replaceable switch per say.

Ah, ok. I'll fire up the laptop running Forscan when it stops raining and see what it says.

 

[Majestic]

The button on the touch screen is just a communicated message to the module under the passenger seat.

Becuase there is a module running the climate controlled seats i bet there is a dtc setting in the module. That module is seeing a fault and tuning off the system. The click you are hearing are relays switching in the module. There isn't a replaceable switch per say.

You mentioned earlier that the module under the seat might have some burned connectors. That's what I was referring to. Is it able to be accessed without removing the seat? Thanks for your help, btw.

 

[Johnbigdog]

You mentioned earlier that the module under the seat might have some burned connectors. That's what I was referring to. Is it able to be accessed without removing the seat? Thanks for your help, btw.

You should be able to remove the four seat bolts, rock the seat back and get to it pretty easily. Not sure how easy it will be bolted in.

Look like I'll be doing the same. My driver seat went out the other day. I know I had a cushion ted that I half asked fixed with tape last year.

 

[Majestic]

You should be able to remove the four seat bolts, rock the seat back and get to it pretty easily. Not sure how easy it will be bolted in.

Look like I'll be doing the same. My driver seat went out the other day. I know I had a cushion ted that I half asked fixed with tape last year.

Disconnect battery for 30 minutes to disarm airbag?

 

[Johnbigdog]

Disconnect battery for 30 minutes to disarm airbag?

If you want. The rcm isn't going to deploy the bag unless it detects an accident or you short the bag circuits.

 

[Majestic]

There was a seat heater overtemp detected, which I cleared and will see if that corrects the issue. The only other DTC is b12d8:13-2a - mirror heater output, circuit open. That comes back each time I cycle the ignition and scan. Wonder what that's about?