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Discussion Starter #1
Can anyone tell me the correct voltage readings for the plug before the a/c control module on a 2000 sts? I would also like the correct readings for the plug AFTER the module that plugs into the blower motor. I have voltage at both plugs, but motor does not run. Replaced both the module and motor, still no blower. Thanks for any input.
 

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2002.5 F55 CORSA STS, 2014 Explorer XLT FWD
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You should have vehicle voltage (key in RUN, ~12.3 engine off, ~14.6 running) at the module input. After the module, there are either 4 or 5 steps in voltage to control blower speed. Probe between the input/motor hot wire and the harness ground wire. Sounds as if a ground has lifted somewhere. Try a temporary jumper from vehicle hot directly to motor hot, which would = high speed. If no joy, temporarily jumper both + and - to the motor. You only get system voltage with the key in RUN. As a last resort, go to your FSM and see if there's a relay in a fuse box somewhere, but you say you do have voltage, so that's really not possible.
 

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Discussion Starter #3
At the module input I have 12v when my fan switch is on high. I have about 6v when the fan is on low. However, when I plug it into the control module, I have 12v on the purple wire to vehicle ground, but nothing between the black and purple wires. That's what's confusing me. I have a new ac control module in it now, but the voltage is the same after the module as it was with the old one in it. Could I have a bad new module? I will try jumping the motor, it's getting hot here in colorado. Thanks for your help, I will keep you posted.
 

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Discussion Starter #4
Well, you were right, it was the ground wire at the ac control module. Ran a new ground.....I have A/C:bouncy: Thanks for the input. This sight is a great resource.
 
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