Trying to understand ac fan switch 82 sc

[avsarinana]

My evaporator blower fan isn't working ... No voltage at the blower fan. no voltage at fan speed control. Fuse is good, (fuse 20) ! still trying to figure out all that controls the electrical circuit .

Thanks !

[walt]

If you didn't remove the fuse and thoroughly clean the contacts I would do that first.

[avsarinana]

Originally Posted by walt

If you didn't remove the fuse and thoroughly clean the contacts I would do that first.

Thanks Walt, that schematic works...everything points to the ac relay.. My fuse is good and has power on both ends. I have no power to the red wire on my blower fan switch . now how to trouble shoot the relay?

I have 5 terminals on the relay- 30-86-87-87A-86- i only have power to 30 and 87A terminals ..

[avsarinana]

Is the ac relay .. the round black one about the size of a quarter in the fuse box area .. the one farthest to the right..I think Im looking at the right relay.

[walt]

Yes, the one closest to the front. Just switch the relay another and see if that fixes it.

[avsarinana]

Originally Posted by walt

Yes, the one closest to the front. Just switch the relay another and see if that fixes it.

I switched the relay it didnt fix it.. i'll have to keep on looking . seems like a simple circuit, but i'm still missing something. If i have a good fuse and a good relay i should have 12 volts at the red wire on the fan speed control.. But i have no power at blower fan switch ?

[avsarinana]

I have no continuity from 87 terminal on relay at fuse box to the red wire on my fan blower speed control....So i have to assume there is break in the wire somewhere in between 87 terminal and fan switch...I do have power to the relay in smugglers box? its the same wire that tee's off to fan switch.

[avsarinana]

I figured out the problem...I appreciate the Schematic you sent me Walt.. Its the relay in my smugglers box thats open and not sending power to my fan switch through wire 87....One problem with the schematic as it applies to my 82 911. the smugglers box relay is the ac relay with the yellow starter wire connected and wires red/white, red, and black.. its marked wrong ! once again the smugglers box relay is marked wrong. smugglers box relay is the ac relay and not cooling fan motor relay.

Thanks!

[avsarinana]