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Old 05-27-2016, 01:10 AM   #1
c10 custom
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Join Date: Aug 2011
Location: Lethbridge Montana
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blowing heat/ac fuse

Hello everybody i am working on a 1984 chev truck and the heat/ac fuse keeps blowing when you put the fan on high speed ? And the Oil Pressure Gauge stays pegged over to the right ? Any help on this would be greatly appreciated thank you
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Old 05-27-2016, 05:18 AM   #2
hatzie
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Re: blowing heat/ac fuse

Download the 1984 wiring diagrams from the manual link in my signature. Option C60 (AC) is the bottom left panel of the right hand block of PDF page 14.

The HI setting doesn't power the fan directly it closes the contacts on a relay on the AC housing in the engine bay.
Either the orange wire from the switch to the relay coil is damaged and shorting or the relay itself is shorting internally. Unplug the switch and relay then ohm the orange wire to a good ground... the meter should read ∞ ( the same as unconnected meter probes ) if it reads anything else the wire is damaged.
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RTFM... GM Parts Books, GM Schematics, GM service manuals, and GM training materials...Please include at least the year and model in your threads. It'll be easier to answer your questions.
And please let us know if and how your repairs were successful.
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