Author Topic: heater fuse keeps blowing  (Read 5540 times)

Offline the_legend_1981

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heater fuse keeps blowing
« on: February 08, 2008, 07:01:47 pm »
I went out and started my truck tonight and there was no heat blowing out. I checked the fuse...blown.  I changed it, it blew again. I'm thinking blower motor is gone, any ideas? 78, glass fuses

Offline the_legend_1981

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Re: heater fuse keeps blowing
« Reply #1 on: February 08, 2008, 07:38:10 pm »
connected it direct...blower not blowing...

Offline VileZambonie

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Re: heater fuse keeps blowing
« Reply #2 on: February 08, 2008, 07:55:30 pm »
What do you mean connected it direct? Be careful, if it's shorted you'll burn the house down. You can simply unplug the ppl wire at the blower motor and replace the fuse. Then see if it blows, if it doesn't you kow the motor is shorted and needs to be replaced.
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Offline the_legend_1981

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Re: heater fuse keeps blowing
« Reply #3 on: February 08, 2008, 08:21:34 pm »
if something is stuck in there the fuse will blow right?

Offline VileZambonie

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Re: heater fuse keeps blowing
« Reply #4 on: February 08, 2008, 09:10:56 pm »
With an electric motor when mechanical resistance increases so will current flow, also contrary to ohms law in a conventional electric circuit, with electric motors when voltage decreases current draw will also increase. So it is possible however just do a quick test like said above and if it passes, take the motor out and inspect. Do you have a digital meter?
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74 GMC, 75 K5, 84 GMC, 85 K20, 86 k20, 79 K10

Offline the_legend_1981

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Re: heater fuse keeps blowing
« Reply #5 on: February 09, 2008, 09:26:32 am »
i cleaned the nest out and put it back in...the blower turns on now but slows down and kills the fuse

Offline VileZambonie

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Re: heater fuse keeps blowing
« Reply #6 on: February 09, 2008, 10:03:29 am »
yeah just replace it, they're cheap anyway, just keep in mind it won't come with a new squirrel cage. If your truck has an AC heater box I have a good one in stock you can have
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Offline the_legend_1981

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Re: heater fuse keeps blowing
« Reply #7 on: February 09, 2008, 10:40:19 am »
no ac, thanks

Offline the_legend_1981

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Re: heater fuse keeps blowing
« Reply #8 on: February 09, 2008, 02:30:15 pm »
put a new blower motor in blew a fuse

Offline VileZambonie

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Re: heater fuse keeps blowing
« Reply #9 on: February 09, 2008, 02:33:51 pm »
Are you talking about the 25A fuse from the junction block? If you unplug the blower motor connector and the circuit is fine but when you hook up the blower motor connector the fuse blows, then you have a defective motor. Did you get a new one or a used one?
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              ⌠ŻŻŻŻŻ'   [☼===☼]
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74 GMC, 75 K5, 84 GMC, 85 K20, 86 k20, 79 K10

Offline the_legend_1981

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Re: heater fuse keeps blowing
« Reply #10 on: February 09, 2008, 03:03:20 pm »
new