Heated Seats No Go

[bjcarrera]

I took my 01' 996 in for its 60K maintenance a few months ago and asked them to look at the passengers’ seat as the seat heater would not work. They came back and said the switch seemed fine but they would have to pull the seat to look to see what else it could be. Needless to say they wanted to charge me a lot.

I have the seat out of the car to do some other things. Is there anything I can look at to see what it could be? I really don't know where to start or what to look for.

:rolleyes:

[djantlive]

check fuse. is there power coming out of the harness? i'd start with that to narrow down the issue.

[Stefan]

I agree with djantlive. The seat heater is basically a big resistor. If there is power going to it then the only reaonable explanation is that there is a break in the heater wire (unlikely IMO). I suspect there is no power which probably means a blown fuse, bad switch, or disconnect in the harness leading up to the seat.

[Dharn55]

I agree with djantlive. The seat heater is basically a big resistor. If there is power going to it then the only reaonable explanation is that there is a break in the heater wire (unlikely IMO). I suspect there is no power which probably means a blown fuse, bad switch, or disconnect in the harness leading up to the seat.

Threre is also a relay under the set which could have gone bad. Do both the seat bottom and back fail to heat? They are separate elements so if both are not heating it would indicate the the problem is not the cushions themselves.

[bjcarrera]

The problem is when I try and depress the seat heater switch on the console it does not stay on, so it is hard to say what does and does not heat up.

The fuse in the fuse box looks fine. The seat is out of the car, how do I check to see if the seating element is working or getting power. Sorry, I am not very mechanically inclined. Is there a tool I can buy that will tell me?

[RedRidge]

The problem is when I try and depress the seat heater switch on the console it does not stay on, so it is hard to say what does and does not heat up.

The fuse in the fuse box looks fine. The seat is out of the car, how do I check to see if the seating element is working or getting power. Sorry, I am not very mechanically inclined. Is there a tool I can buy that will tell me?

That switch will only latch the relay of the heater, the heater power will not go through this swicth. If you hear relays clicking when the swicth is depressed then that part of the circuit is good. Next step is power feed to the relay that powers the seat.

I would check resistance on the bad seat, if your not reading any ohms (resistance) then that heater is open (no good). If you have resistance I would compare it to you drivers seat. If the resistance is similar to the good seat then it is not your heater and should be wiring and should check for power issues. GL

Edited February 21, 2007 by RedRidge

[Stefan]

I don't think I've ever heard the click of the seat heater relay so I wouldn't rely on its audibility. I recommend you swap in the driver's side seat heater relay and see if the problem is fixed. If so, then you just need to get a new relay.

[Dharn55]

Again, the heater elements for the seat cushion and the backrest are separate parts, so if one is bad, the other should be working, it would be unusual for both to go bad at the same time. Problem is probably in the relay or the wring/connections. Swapping the relay is a good idea. Also, go to www.dennisvogel.com and look in his boxster section for the article on adding heated seats. It has all the wiring diagrams, illustrations, part numbers etc., which could be helpful to you in diagnosing the problem. I used this article with some mods to add heated seats to my 996.