Seat Heater stopped working

So it's getting colder outside and I just noticed my driver seat heater is not working.

 

Passenger seat heater is working fine.

 

I checked cables under the seat and nothing appears to be loose or unplugged. Looked at the manual at the fuse layout ... but there is only one fuse for seat heaters, and since passenger seat is working can rule out the fuse.

 

This leaves the seat itself. Unless someone has anything else for me to check.

alot of the seat heaters get bunched up inside the seat over time and when it doesn this the wires pull out of the back of the heater.

 

I just installed STI seats into my outback XT. When I took the seat apart to move the heaters over to the STI I had one that was barely hanging on.

 

The seat heater is 111.00 from Subaru. About 80 from Fredbeans.com.

 

To change it out you have to remove the seat from the car, remove the seat back and then take the fabric/cushion off. Its only some platic clips on the bottom side of the seat frame that hold this on. Its best to have the seat extended up if you have the manual seat lever on the side.

 

There are hog rings you run into when you start to peel the fabric up. I just opened them up with needle nose pliers and then bent them back into shape with small channnel locks after changing the heater.

 

Good luck.

Oh and if you have access to a multi meter, you can unplug the seat heater under the seat and either measure the resistance of the to pins or use a continuity beeper to see if you get a connection between the pins on the cable going up to the seat. I think it should read about 7.8K ohms

Here is a how to to get the seat heater out of the seat. I used this when doing my STI seats.

http://legacygt.com/forums/showthread.php/install-heated-sti-seats-into-lgt-reletively-painless-103465.html

Thanks gregnauman! I'll try your suggestions.

Oh and if you have access to a multi meter, you can unplug the seat heater under the seat and either measure the resistance of the to pins or use a continuity beeper to see if you get a connection between the pins on the cable going up to the seat. I think it should read about 7.8K ohms

 

I'm having the same problem as the OP stated, but my passenger seat isn't working. Here's what I've done thus far:

 

Measured the resistance between what I think is the seat heater (can you confirm based on the attached picture? it's the one unplugged)... it's a four wire connector with the following wire colors:

A-White

B-Brown

C-Black with Red

D-Black with Red

 

Resistance from: Continuity (Y/N)

A to B = 3.1 ohms Y

C to D = 17.3K ohms N

A or B to C or D= Open N

 

This connector (what I think to be the seat heater, again please confirm) plugs into a four wire plug on the car's side with the following colors:

A-White

B-Blue with White

C-Red

D-Blue with Red

 

where:

Continuity (Y/N)

A to B = Y

C to D = N

B to D = Intermittent

 

I also have power once the ignition is partially on (10 v on Blue with white and 12 v on white). These voltages do not change when the heat levels are changed.

 

So basically at this point I'm not sure what to think... If Scooby 2.5 is right and the heater should be about 7.8K ohms then I probably have a wire pulled loose at the plug inside the seat or the sensing element is bad. Any suggestions on my next step? I'd rather not purchase a new sensing element or pull the seat apart if I don't have to...

I'm having the same problem as the OP stated, but my passenger seat isn't working. Here's what I've done thus far:

 

Measured the resistance between what I think is the seat heater (can you confirm based on the attached picture? it's the one unplugged)... it's a four wire connector with the following wire colors:

A-White

B-Brown

C-Black with Red

D-Black with Red

 

Resistance from: Continuity (Y/N)

A to B = 3.1 ohms Y

C to D = 17.3K ohms N

A or B to C or D= Open N

 

This connector (what I think to be the seat heater, again please confirm) plugs into a four wire plug on the car's side with the following colors:

A-White

B-Blue with White

C-Red

D-Blue with Red

 

where:

Continuity (Y/N)

A to B = Y

C to D = N

B to D = Intermittent

 

So basically at this point I'm not sure what to think... If Scooby 2.5 is right and the heater should be about 7.8K ohms then I probably have a wire pulled loose at the plug inside the seat or the sensing element is bad. Any suggestions on my next step? I'd rather not purchase a new sensing element or pull the seat apart if I don't have to...

 

Yep you are correct:

 

wire connector with the following wire colors:

A-White

B-Brown

C-Black with Red

D-Black with Red

 

 

A little ways down this cable going up to the seat (not the wiring from the floor harness) it has a green connector coming off it with Blue and White wires for the seatback heater.

 

When I measured mine, when it was working it seemed it was about 7.4 ohms.

 

What I would do is trace the wire back and find the green connector and unplug it.

 

Then measure the resistance/continuity between the four pins you listed. If you get nothing its the seat bottom heater.

 

Then measure at the green connector going up to the seat back and see what you get.

 

If it has continuity it should be fine.

 

Most of the time the failure is in the seat bottom.

 

So coming out of the seat bottom heater you have a wire with a white connector that goes into the floor harness. This is the white connector with the blue tape in your picture. The white connector still on the seat is the one that goes to the seat bottom cushion. If you unplug this from the floor harness, like you did in the picture and follow the black wire up you will find that it has a Splice off this wire with a green connector with a blue and a white wire that goes up to the seat back. Once you disconnect from the floor, and disconnect the green connector, you can check continuity of both seperately.

 

 

 

Hope this helps

Thanks man.

 

I found the green connector (was one of the four wires that I was checking originally), it has continuity and had a resistance of 7.4 ohms (not K). The other two wires (I think they're for the top) have a shield around them all the way under the seat. I'm guessing if I pull back the plastic on the back side of the seat that it will be right there. That said, how do you get the plastic on the back of the seat off, do you just pry it off? It doesn't seem to want to come off for me...

 

You also confirmed what I was thinking-that there are heaters for the back and the ass. I honestly think the back heaters have never worked on either one of my seats!

Yep I have a tool sort of like a screw driver that is angled to pop door panels off.

 

You just place something like that under the edge and pry up and it pops off.

 

Yea I meant 7.4 ohms.

 

If you have continuity at the green connector then the seat back should be fine.

 

If that is the case I dont think you need to take the seat back off.

 

So its probably the seat bottom thats bad.

 

fredbeansparts.com has them the cheapest at right around 80 bucks. Retail is 111-130.

Yep I have a tool sort of like a screw driver that is angled to pop door panels off.

 

You just place something like that under the edge and pry up and it pops off.

 

Yea I meant 7.4 ohms.

 

If you have continuity at the green connector then the seat back should be fine.

 

If that is the case I dont think you need to take the seat back off.

 

So its probably the seat bottom thats bad.

 

fredbeansparts.com has them the cheapest at right around 80 bucks. Retail is 111-130.

 

Yea, I have the same tool, but it really doesn't seem like you can just pull it off (and I'm afraid I'm going to break it). Good thing I don't have to do it...right now.

 

So what you're saying is that if the bottom seat heater is disconnected the small green connector with two wires (the only one underneath the seat), will read open/no continuity.

 

If the heating element is bad (as long as the failure mode isn't shorted, and that wouldn't be likely unless it's just disconnected or something cut the wires), the reading would be significantly different than 7.4 ohms?

 

Of course this should then also be the same for identifying if the back heater is working as well except that the connector would be on the back side of the seat underneath the plastic.

 

I appreciate your help and just trying to make sure I (and anyone who reads this in the future) understands exactly what to look for.

Here is a run down....

 

1. Yes the back plastic just pops off, a little force is needed and it has quite a few clips all around it.

 

2. After you disconnect the bottom seat heater from the Car wiring harness you have this (pic below) wiring clipped to the bottom of the seat.

This is the wiring that is part of the BOTTOM Seat Heater element blanket. I had just cut the element blanket off as it was bad.

http://gallery.me.com/gregnauman/100042/IMG_0179/web.jpg

 

3. In the picture above the green connector plugs into the Seat BACK heater to feed the Seat Back heater blanket which also is a green connector. The White Connector goes to the floorboard wiring harness white connector. When you unplug the seat BACK heater from the above wiring harness and measure the resistance of the green plug going to the seat back heater you UNPLUGGED from this wiring above you should have around 7.4 ohms. Each element whether bottom or seat back should be about 7.4 ohms near as I remember.

 

4. Once you have the green seat back connector disconnected from the above wiring, you can measure resistance across each of the 2 sets of pins in the white connector in the above picture and 2 of them will be open due to the seat back being unplugged but 2 should have resistance/continuity (not open) for the seat bottom heater blanket.

 

5. The wiring above is clipped to the bottom of the seat and runs out the back. The seat back element ties into the seat bottom element at the green connector goes out the back of the seat and up into the seatback.

 

Again the picture above is the SEAT BOTTOM heater wiring MINUS the actual heater blanket, as I cut off the old one that was bad. If you order a new seat bottom element it will look just like the picture but will have a heating element blanket attached to it where the bare wires are.