99 STS both front heated seats stopped working. First was my passenger changed the "heated seat control module" from directly under it and still same thing. both fuses are perfect..both switches work hi-lo as they light up and send electric to module (hear click on & off) then a few days back my drivers just stopped working but still hear click on and off. Where do i go now?

 

i am having the same prob on my 98 sls with the driverside not working as i also hear the clicking on and off noise. so if any body can help the freezing please do as it is getting colder lol. Yes im a P^ssy when it comes to the cold.

 

Here's some troubleshooting instructions for the front heated seats:

Step 1: Disconnect connecter C1 (8 cavity) from the heated seat module. Check voltage between cavity B (orange wire) and chassis ground. You should get 10-15V. If not, and presuming fuse is good, fix open in orange wire between rear fuse block and heated seat module connector.

If you get 10-15V in Step 1:

Step 2: Check voltage between cavity B (orange) and cavity E (black). You should get 10-15V. If not, repair open ground in black wire.

If you get 10-15V in Step 2:

Step 3: Turn ignition to on position. Check voltage between cavity A (brown) and chassis ground. You should get 10-15V. If not, fix open in brown wire between rear fuse block and connector.

If you get 10-15V in Step 3:

Step 4: Turn ignition off and check resistance between cavity C (purple-Left seat or purple/black-Right) and chassis ground and press the appropriate heated seat switch. You should get less than 5 ohms of resistance. If so, disconnect heated seat module connector C2 (4 cavity) and C3 (2 cavity) and measure resistance between the two connections in C3. It should be 1.5 - 10 ohms. If not, replace seat back*. ALSO, check resistance between cavities A and B of connector C2. (All wires in C2 are black, cavities A and B are in line with the rounded end tab.) Resistance should be 1.5 - 10 ohms. If not, replace the seat cushion*. If you got the proper 1.5 - 10 ohm resistance for BOTH, check resistance between C2 cavities C and D (in line with the square end tab). Resistance should be 850 - 1150 ohms for a COOL seat cushion. If not, replace seat cushion*. If it is 850 - 1150 ohms with cool seat, replace the heated seat module.

If resistance was NOT less than 5 ohms at beginning of step 4:

Step 5: Disconnect the appropriated heated seat switch connector. Check resistance between pink (or pink/black) cavities in both connectors (controller and switch). Resistance should be less than 5 ohms. If not, fix open in the pink (or pink/black) wire.

If resistance was less than 5 ohms in step 5:

Step 6: Connect meter between pink (or pink black) and black of the heated seat switch and press the switch. Resistance should be less than 5 ohms. If not, replace the switch.

If resistance less than 5 ohms in step 6:

Step 7: Fix open wire in ground (black) wire leading to heated seat switch.

*The heaters are integral to the covers and cannot be repaired or replaced, and the leather covers are far from cheap. I do though believe that GM makes (or made) add-on heaters that can be applied over the originals but cannot find them in any on-line catalog. You'll probably have to see if they're available through a dealer.

 

With the few (very few) seat heaters i have seen that did not work after all the "normal" things where checked (like in above post) was just cracked wires. Not sure you would call them wires as they are sorta flat. The problem with repairing them is the material used is so thin that its not easy to reconnect. I have seen people try the rear window defog kits. Problem is you sit on it and it flexes, alot. I would think somebody could come up with something with some thought. There are aftermarket ones, just a pad that goes under the cover, that would be the cheapest

http://www.checkcorp.com/seat-heater/seat-heater.asp

about $200 shipped for both front seats if you are a DIY man.

Of course make sure its an actual problem first, do all the checking suggested. And keep in mind there is credible research (depending on what you belive is credible)that forus guys,heating up Jonny and the boys can actualy do some harm if you plan on rugrats.

 

Wow thanks for input guys.ima try to take a saturday after all these holidays and stuff and check wires and readings..etc...

 

A good how to replace element at: http://turbojimmy.4t.com/DTS/heatedseats.html