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AC/Heater fan not working

  #1  
Old 06-26-2008, 02:18 PM
stevel's Avatar
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Default AC/Heater fan not working

Hello,

I've got a 97 Civic and the fan is not working on the AC/Heater. The AC works - as does the heat - air will force through the vents while driving and blow hot or cold, but the fan does not turn on.

For a long time, it only stopped working intermittently, Then it started not working when it gor extremely hot or extremely cold (of course). Later, it would come back on when I hit a bump or ran over a railroad track.

Lately, it's just not worked at all.

Recently, I took it in for inspection and they said I needed an "AC Motor Mount" which apparently meant the motor mount on the "AC side" of the motor. My thinking is, if the motor mount was loos/broken, hitting those bumps may have been hitting the AC fan motor and that's why it would come back on.

Anyways, it sounds like it could be simply aloose connection that's finally come all the way loose. Anyway, what I want to know is if there's any way I can check? I don't even know where any of that stuff is! Is the AC fan motor accessible from under the hood, or is it a take the dash out kind of thing?


TIA
 
  #2  
Old 06-26-2008, 02:45 PM
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Location: Houston, Texas
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Default RE: AC/Heater fan not working

The A/C motor mount is likely a separate unrelated issue.

It sounds like the condenser fan (next to radiator fan) is fine and that the blower motor (passenger front side just behind glove box) or its circuit is the problem.

1) Start by supplying battery power directly to the blower motor. If it runs, the problem is with the circuit (steps 2-4). Note whether the blower connector is loose.

2) Check whether fuse no. 55 (under-hood) or no. 17 (under-dash) is blown or loose.

3) Check whether the blower motor fan relay in the under-hood fuse relay box is faulty.

4) Check whether the blower resistor or blower switch is bad.

For details, see link to the 96-98 service manual in my signature.
 
  #3  
Old 06-26-2008, 06:38 PM
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Default RE: AC/Heater fan not working

Look up under the dash on the extreme right side of the car. You will see a cylindrical part on a black plastic flange which is the bottom of the motor. Plugged into it is a 2 wire plug, the power for the motor. Turn the key on and set the fan on high and measure the voltage between the 2 wires. If you have approximately 12 volts there but the motor doesn't run, the motor is bad. I think you can take the screws out and R&R the motor without taking any of the dash apart.

If you have zero volts keep checking the fuses, relay, switch, and resistor.
 
  #4  
Old 06-28-2008, 08:20 AM
stevel's Avatar
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Default RE: AC/Heater fan not working

Ok, thanks for the "dummy" explanation (which I sorely need).

I'll check the voltage and see what's going on.

Thanks,
Steve
 
  #5  
Old 07-01-2008, 12:36 PM
stevel's Avatar
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Join Date: Jun 2008
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Default RE: AC/Heater fan not working

Thanks Guys!

I was able to remove the old fan, troubleshoot, and bought a new one and replaced it myself.

I feel both a sense of accomplishment and a sense of cool!!!

Thanks again.

Steve
 
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