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Discussion Starter · #1 ·
Hey Guys, I'm trying to get the blower working on this factory a/c car. Now, some past bozo owner removed the a/c hoses, compressor, poa valve,and the a/c water valve. All the wiring is in place, but the 4 prong blower resistor was gone. I found a used one, but no quite sure if it works. When I plug it in, I hear a "clunk" type sound like it's energizing something in the evaporator box. Problem is, the blower motor still will not work and the battery goes dead after a week. Anyone run into a situation like this before? Thanks, Brian :confused:
 

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It's possible that the noise "I hear a "clunk" type sound " is the high speed relay picking up which would, if left on, drain the battery. Grab a volt meter or a test light and check the wiring.

The resistor connector will have yellow, light blue, light green and dark blue wires. With the speed switch in the low position you should have power on the yellow wire, in the med 1 position you should have power on the light green wire, and in the med 2 position you should have power on the light blue wire. Each of the three mentioned wires connect the resistors then out the dark blue wire, which is spliced the purple wire which connects to the blower motor. Now for the high speed relay. When high speed is selected voltage is applied to the dark blue wire in the high speed relay connector, the orange wire in the connector always have voltage (10 gauge black wire connects to the horn relay and to an inline fuse to the orange wire) the purple wire, spliced with the dark blue wire from the resistors, connects to the blower. Last but not least, the high speed relay has a separate black wire it is the ground, the A/C harness has a black wire that connects to the firewall, it's the ground point for the relay. The blower motor also has a black ground wire that is spliced to the relay ground.

So basically the three lower speeds supply voltage from the dash harness to the blower motor through resistors. High speed picks up a relay to supply voltage from the horn relay to the blower. Both the blower motor and the high speed relay ground to the firewall.
 

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Discussion Starter · #3 ·
Thanks, I'll give that a try today, Brian
 
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