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Old Jun 16, 2012 | 02:30 PM
  #1  
menardd's Avatar
menardd
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Default fan speed

1975 coup anyone know why my ac heater fan switch will not go to high speed? It starts at low , goes to medium , then goes to next speed but when it push it all the way to the right , on more click shuts off. I have changed the resister, the relay , and change the fan motor and squirrel cage. What else is there?
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Old Jun 16, 2012 | 05:32 PM
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From: grand prairie texas
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If your 75 is the same as my 77 there is a high blower relay that mounts on the top of the A/C evaporator box
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Old Jun 16, 2012 | 06:01 PM
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From: mount holly NC
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Default Is 75 the same as 74?

You might have a bad inline fuse. Look under the left fender near the M/C.
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Old Jun 16, 2012 | 06:42 PM
  #4  
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Default fan speed

THanks I just look at relay took the cover off and touch down the contact point and the fan went on, high speed, So I bought a new relay and same problem .Fuse is good, put a new one in.
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Old Jun 16, 2012 | 08:13 PM
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Originally Posted by menardd
THanks I just look at relay took the cover off and touch down the contact point and the fan went on, high speed, So I bought a new relay and same problem .Fuse is good, put a new one in.
The blue wire at the relay needs to be hot when the fan is on high AND the relay case needs to be grounded.
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