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Hello all, have a problem with my seat heaters and wondering if any one has experince with these? My car 90' SEC has power going to switchs and power going to the relay under the seats but cant get the heaters to work, and no lights on the switches? Both seats are not working so it doesnt seem that both relay's would go bad at the same time and the relays are expensive to buy and (test) to see if that is the problem. And yes the fuse is OK. Unless there is another fuse somewhere?

I have a 86 donor car with heated seats and the relay is different...:( Any other ideas to test would be a big help.

thanks, Scott
 

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a device that is designed or used to transport people or cargo.
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I am no expert, but I recall reading somewhere that the circuitry senses battery condition and will not heat the seats if the electrical supply is weak, so as to not leave you with a dead battery.

Put a charger on your battery then see if they work under that circumstance?
 

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1989 560SEL, 1979 Cressida MX32, 2006 F150 Lariat
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There are 2 fuses and 2 relays. The front seats have one fuse/relay and the rear seats have another fuse/relay. The relay for the front seats is located under the driver seat near the floor. Do the rear seat heaters work? Chances are that water build up in the floorboard from whatever reason, be it a leaky sunroof drain or deteriorated evap drain tube, thus has ruined the relay, that is what happened to mine. I would pull the relay and open it up. If the circuit board is corroded you can see it very clearly. There is no way to repair something like that in such corroded condition and you will have to replace it. The relay from your'e 86 parts car will not work. I will save you some part searching time by saying that 1989 to 1991 ONLY. SEL/SEC relays will work. The part number you are looking for is 000 820 6226 12V SG 601.645 or you could use the relay from the rear seats but you would need to remove the seats in order to get at the relay. The 2 fuses are located on the ouside edge of the fuse box and to the right near the fender. If you have power as mentioned in the OP, then I would suspect it to be the relay. move the driver seat all the way forward and tilt the bottom all the way up, you will then have easy access to the relay. Hope this helps you get them fixed.
 
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