Author Topic: AC blower motor blowing fuse  (Read 3165 times)

Offline LosT_HaVoc

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AC blower motor blowing fuse
« on: May 07, 2015, 04:10:08 pm »
Right now, I'm stuck in my college dorm, 300 miles away from my truck, but any ideas are helpful. I've replaced the fan speed switch and the resistor pack for the blower motor on my '87. Even after all that, it still blows the fuse when I turn on the fan. What could be wrong with it?
Proud owner of 1987 C10 & 1973 C65 Custom Deluxe
Just because I work on tractors doesn't mean I don't know anything about trucks.

Offline bd

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Re: AC blower motor blowing fuse
« Reply #1 on: May 07, 2015, 04:21:50 pm »
What happens if you simply unplug the power wire from the blower motor?  Does it still blow the fuse?
Rich
It's difficult to know just how much you don't know until you know it.
In other words... if people learn by making mistakes, by now I should know just about everything!!!
87 R10 Silverado Fleetside 355 MPFI 700R4 3.42 Locker (aka Rusty, aka Mater)

Offline LosT_HaVoc

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Re: AC blower motor blowing fuse
« Reply #2 on: May 07, 2015, 04:37:39 pm »
What happens if you simply unplug the power wire from the blower motor?  Does it still blow the fuse?
Haven't tried that yet. But I'll try it. Thanks
Proud owner of 1987 C10 & 1973 C65 Custom Deluxe
Just because I work on tractors doesn't mean I don't know anything about trucks.

Offline Irish_Alley

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Re: AC blower motor blowing fuse
« Reply #3 on: May 09, 2015, 07:47:30 am »
can you even spin the motor by hand? voltage and amps to a motor depend on the resistance, so if a motor is hard to turn then the amps will rise or you have a short
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Offline VileZambonie

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Re: AC blower motor blowing fuse
« Reply #4 on: May 09, 2015, 08:42:42 am »
What happens if you simply unplug the power wire from the blower motor?  Does it still blow the fuse?
Haven't tried that yet. But I'll try it. Thanks

This is where you should have started prior to replacing any parts. By disconnecting the load in the circuit you can easily determine if that component is causing the high current draw. Do this and bring a test light or meter to verify the integrity of the circuit.
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