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Posted by: mtndawg Dec 23 2012, 11:59 PM

I picked up a 914 a couple of weeks ago and am now sorting through it to get it on the road. Today I cleaned up the throttle body and put it back into the car, while I was idling, I pulled the heater lever and it killed the electrical, I put lever down and started the car once more, again pulled the heater lever. The second time, the electrical went out, now I'm not getting any power. What could cause this?

Posted by: mittelmotor Dec 24 2012, 12:04 AM

That lever contains a switch that powers the heater squirrel-cage fan in the engine compartment. Apparently there's a short in the circuit.

Posted by: SirAndy Dec 24 2012, 12:08 AM

The heater blower circuit is running through the same fuse (on the relay board) as the fuel pump.

Check the fuses on your relay board. One should be blown. Then find the short in the heater blower/lever circuit.

Posted by: steuspeed Dec 24 2012, 12:10 AM

Check the relay on the engine compartment relay board. IIRC it's the one at the bottom of the board or the one furthest toward the back of the car. Mine just went out, and I replaced it with my fog light relay from under the dash to get by. There is also 2 fuses on the board. The small one is for rear window defrost (most cars don't have this) and the othe one is for everything else on the board. You might have popped that. You can also unplug the fan in the engine compartment and hook it up to the battery with some wires to see if it runs okay.

Posted by: kg6dxn Dec 24 2012, 12:16 AM

The lever sends a ground to the blower fan. If your fan is bad, you may have sent a direct short to the electrical system.

Most likely a blown fuse(s) somewhere. Make sure the correct size fuse is installed OR the wiring will turn into the fuse...

Posted by: 76-914 Dec 24 2012, 01:57 PM

Did you run 12v + to the "Heat On" indicator light?

Posted by: drdave427 Dec 24 2012, 06:18 PM

Forgive my ignorance -- where is a "heat on" light ?? Is that the same as the defrost light by the heat lever ???

Posted by: 76-914 Dec 25 2012, 10:29 AM

yea, that one. but judging from your response you obviously didn't.

Posted by: Tom Dec 25 2012, 12:18 PM

Clarification for the relay board fuses.
The front fuse is for use on Sportamatic cars.
Rear fuse powers fuel pump, AAR, rear window defroster, and heater fan.
most folks use the front fuse holder to keep a spare fuse in.
Although the Haynes manual calls for a 25 amp fuse, if you are not running a rear window defrost, use a 16 amp. I don't have my heater fan in and only run an 8 amp. Always use the lowest amp fuse that the circuit will allow.
Fuel pump is about 5 amp, heater fan about 5 amp, AAR is about 1.5 amp. So a 16 should be fine.
Tom