cobalt

Did a search came up with nothing. I am working on someones 964 and the heated seats aren't working.

I followed the procedure in the workshop manuals. Everything is working. Switch gets proper voltage still no heat. When I test for resistance on connector # 3 per the manual I am getting full continuity so no resistance which would explain why no heat is being generated.

I am assuming this means the coils in the seats are NG. Not sure how this could happen but am I heading in the correct direction. None of my 911's ever had heated seats so I am at a loss with this one.

DobermanDad

Mine also stopped working. Interested in seeing what is said about this.

HiWind

mine too (on the 993)

crg53

I have heated Seats in mine as well, but never used them. Should try them out, does the engine have to be running for the seats to work??

cobalt

No AFAIK only the key needs to be in the accessory position.

deadendd9009

Heated seats draw quite a bit of current, I'd have the engine on.

My heated seats don't work either, I was guessing the element had burned out.

Nor911

My heated seat doesn't work as well, has anyone ever opened a heated seat and know if it's possible to change the heat elements?

cobalt

I find it strange nobody has any answers for this. I am sure it is a common problem.

These are just resistance coils so why would they loose resistance? If they burned out I would assume there would be no continuity but instead I have 100%.

Any electrical engineers around here?

pcarfan944

Mine don't work either. With the power switch out of sight (out of mind) I just assumed they were probably left on year after year and eventually burned out.

968norway

I have functioning heated seats. I haven't checked to see if they are on without the motor running, but when the motor is stopped the seats get switched off, so when you restart the engine the seats have to be switched on again.

GeorgeK

No an electrical engineer, but no resistance means continuity, therefore the heating element is functional.
I would suspect the switch. It i went bad on my car. Expensive.

cobalt

Every bit helps. That was my initial thought but everything checks out. The switch shows 5 volts between the ground and red wire and between 2 and 3 volts for the yellow (variable dial) when switched on and rotated. 0 when switched off according to the manuals this would mean it works properly the relay also seems to be working properly. According to the manual if I test the #3 wire I should see between 1.5 and 1.8 ohms but that I am not seeing although there is 100% continuity though.

There is no mention of any resistor or anything so I am at my limit of trying to figure this out since it sounds as though they should be heating but they are not.

klr10

The 1.5 to 1.8 ohms is the resistance of the element. This would rate them at around 8 amps or 100 watts at 12V

mauro6569

My work now, was burned big internal diode relay under the seat