Electrical issue with wiper and heater motors

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Sep 03, 2010 18:50:58
11590

I have a 72 B and I thought I had all of the electric demons chased out and have been at this for a while tonight. Thought I would take a break crack a cold one or two maybe more beers ... it is Friday, and ask for some help.

All other electric circuits work and so did these back in early summer. The only thing I have messed with was removing and servicing the spedometer and it had two grounds connected to the back. I did check those and they seem ok. I have run the electric diagram and the wiper motor and heater fan have the same common ground and power to both the green pink wire. I have also ran an indepentent line power to the fan and the wiper motor and they work.

There are several other lights that share the common ground and they work. Since both systems are affected I do not think it is with the wiper switch, which I removed and cleaned just to be sure. I also cleaned and check the fuse box connections.

Now I am out of ideas and help would be appreciated.
thanks in advance,
mike

Sep 03, 2010 19:44:31
ClayJ

Mike,
Do you have power at the connector for either motor? That would be Green-Yellow at the heater motor; the wiper motor's green-pink supply's power for the homing circuit. All this is powered when the ignition is <on>.

There is a fuse where the green-white from the ign switch joins to the green-pink.

Your radio should be on the green-pink circuit but I wouldn't trust that the radio is wired per factory recommendation. The green-pink to the radio has its own fuse (if still present). Might check radio wiring as it always gets bastardized.

Your screen washer motor is also on this circuit.

Start at one of the motors and work backwards to the switch.





Sep 03, 2010 20:09:22
11590

Clay, No power at either motor, with ignition on and coil disconected. Screen wash motor works when I push the wiper handle in, like it should. No radio, I removed the radio amd all of those wires the PO had with it, a real mess. Things did work after the radio was removed.

Is the fuse off of the green-white wire under the dash or by the fuse box? I am done for the day.
thanks, mike

Sep 04, 2010 08:00:36
11590

Follow up. Problem solve. Clay got me thinking about the green-pink wire behind the radio and it was cut and used by the PO for the radio install and when I removed the radio I did not reconnect. Now off for a drive in the amazing cool crisp sunny day.
Mike

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