I have 1991 190E 2.6 and blower motor doesn't work in system. If I put battery leads on it, it works fine. Any suggestions? No voltage to the motor. TIA

DO YOU VOLTAGE TO & FROM THE BLOWER REGULATOR?

Yes, I have voltage at the switch. There's a ground, 12 volts, and the switch is adding other wires with 12 volts as it steps up the current to the blower. I checked it with a VOM. There are two relays inside the switch, also and at least one activates when I throw current to it. Could the resister pile behind the battery be faulty? A Mercedes mechanic said he has NEVER had one of those go bad. The blower motor runs great with a battery positive put to it using the ground supplied by the wiring. Thanks, Ernie in Louisville

Thanks for the reply. The problem was the bottom plug going into the resister array for the blower was unplugged! What a hassle. It's fixed.