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Heater blowing fuses

jeigen

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my 69 roadrunner a/c and heater is blowing fuses every time I turn it on. Heater box and all wiring is new.
 

Carl Ray

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Does the fuse blow immediately upon hitting one of the selector buttons? Does the fuse blow if you have the blower motor unhooked? What position is blower motor switch in when issue occurs? Is the time delay relay still hooked up?
 

jeigen

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fuse blows immediately regardless which selector I push. Have not tried disconnecting blower motor, but I removed it and put 12 volts to it and it ran fine. Relay is new and hooked up.
 

Carl Ray

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Have you inpsected or done anything with the AC/Heater controller? There are two fuses in the circuit, one for the blower motor and the other for the AC controls, which is blowing? I would disconnect the 6 wire harness from the AC controller and check the pigtails Tan, Black, and Brown wire for shorts to ground. The black is feed so its probably okay since the fuse doesn't blow til you hit a selection. The selector should turn on the blower, without moving the blower motor speed control, but it does feed the tan wire to the blower switch, so while you have the harness apart, remove the 3 wire blower motor harness and check for grounds between the ends of the tan wire on the 6 wire and 3 harnesses. Do you have the electrical diagram?
 

quikbird

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If it. BLows that fast there is a dead short somewhere. Just have to find it. Bad wire or something hooked up wrong. Good luck with the search.
 

jeigen

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i replaced the controller as well. I will have double check on which fuse is blowing. I have not messed with it in a while. I will check for shorts. Thanks for the advise.
 
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