interior fan, 02 vert
Thread Starter
Instructor
Joined: Jul 2007
Posts: 116
Likes: 0
From: Prince Frederick maryland
interior fan, 02 vert
My interior fan works for periods of time then not at all. It will start up sometimes when I hit a bump in the road. I have bench tested the fan and it works great there. I have cleaned the connectors at least five times. It will work for around a month after cleaning then not work intermittently again. A little history: three years ago condensation system backed up and flooded the floor. Nothing fried but the area got wet. After that is when the fan issue started. Very irritating when you need defrosters and fan does not work. BTW, ac and switch to select air location works. Just no fan to push it out the vents. At speed the ac works because there is enough air pressure to push it through the vent. Stop and go traffic nothing. I have put a test light on connector when fan is out of car and it lights. Nothing else that I know of is intermittent on car. Any clues???? 
Tech Contributor
Joined: Jan 2007
Posts: 19,470
Likes: 1,170
From: Dyer, IN
My interior fan works for periods of time then not at all. It will start up sometimes when I hit a bump in the road. I have bench tested the fan and it works great there. I have cleaned the connectors at least five times. It will work for around a month after cleaning then not work intermittently again. A little history: three years ago condensation system backed up and flooded the floor. Nothing fried but the area got wet. After that is when the fan issue started. Very irritating when you need defrosters and fan does not work. BTW, ac and switch to select air location works. Just no fan to push it out the vents. At speed the ac works because there is enough air pressure to push it through the vent. Stop and go traffic nothing. I have put a test light on connector when fan is out of car and it lights. Nothing else that I know of is intermittent on car. Any clues????
Tech Contributor
Joined: Jan 2007
Posts: 19,470
Likes: 1,170
From: Dyer, IN
Ok. The output of the blower motor control processor is ~4-12 volts(depending on fan setting). The blower motor plugs into the blower motor control processor. The control processor provides a switched ground to the motor, and controls the voltage output to change the blower motor speed. With the system on, check for the following:
Blower motor control processor- pin B, 12 volts, red wire, hot at all times.
Blower motor control processor- pin A, resistance to ground, black wire
At the blower motor connector - pin B, resistance to ground, black wire
At the blower motor connector - pin A, ~4-12 volts, purple wire
With everything connected, you should also be able to backprobe pin C of the control processor(with reference to ground), and see a small change in voltage when the fan speed is changed on the control head.
Blower motor control processor- pin B, 12 volts, red wire, hot at all times.
Blower motor control processor- pin A, resistance to ground, black wire
At the blower motor connector - pin B, resistance to ground, black wire
At the blower motor connector - pin A, ~4-12 volts, purple wire
With everything connected, you should also be able to backprobe pin C of the control processor(with reference to ground), and see a small change in voltage when the fan speed is changed on the control head.
Thread Starter
Instructor
Joined: Jul 2007
Posts: 116
Likes: 0
From: Prince Frederick maryland
Thanks. The system works perfect when it is working right now it is all the time cause I just cleaned the connector. I want to check that voltage on pin c when it is not working. That should tell me if the connector is the problem. I know something is loose cause it kicks in going over bumps.
