Wife complained that the seats won't heat in her 1995 E-320.
Fuses are good,when you turn the switch on, lights turn on, but
no heat.When you turn them off I hear clicking in back seat area.
Any help would be appreciated,my rear end is getting chewed up,
becuase hers is not heated up!! Also I get a code 17.Something
about not transmitting data.This has been on about 3 months.
Thanks.

The heated seat control module is located under the rear seat. The last I heard the unit costs $300 to replace. I repaired mine by replacing the relays ($14 for two), which were fried. After three years, the repair still holds.

Where did you get the relays??

I got mine from a local electronic supply house. They happened to have it on the shelf. It wasn't a perfect fit. I had to modify one of the connectors to the circuit board on each relay.

Did you check the 25 amp fuse in the auxiliary fuse holder? As of model year 91 two fuses powered the heated seats. Fuse A in the fuse panel and the 25 amp mounted external to the electrical center.
Pin 1 of the Heater Control module (under the back seat) should have battery at all times and pin 3 should be hot in Accessory, Run or Start. Pin 9 is ground. Modules before MY91 had a different pinout.

Does any of this apply to the 210? My seat backs heat up but the bottoms do not. I thought it was strange for both bottoms to stop heating at the same time.
I have replaced the fuses and no luck. Any help is appreciated.

__________________
Donwo
1999 SL 500 Sport (30K miles)
1998 E320 (SOLD)
1989 560SL (SOLD)
1987 300E (TOTALED)
1986 300E (SOLD)
1984 300SD (SOLD)