heater fan non-operational

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buzz13
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heater fan non-operational

Post by buzz13 »

I was driving the other day and it just stopped. It made no noises before quitting. None of the speeds work. I see posts where only the high speed remains but none of mine work. Checked fuse and it is ok. Are there any other things to check before going to the trouble of pulling the swithch out?
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John Brennan
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Re: heater fan non-operational

Post by John Brennan »

Check the wiring behind the battery, which is vulnerable to corrosion, and check your grounds. Mone recently started working again after I did some work on the EGR tube and I found I had had a bad connection.
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thebronze
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Re: heater fan non-operational

Post by thebronze »

Check the connection on the fan itself.... Mine had "corroded" to the point that it wouldn't either.... Had to clean and use dilectric grease on it....
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buzz13
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Re: heater fan non-operational

Post by buzz13 »

fixed; it was heavy corrosion on the connector; replaced connector but had to splice in some more wire since there is no slack on that single wire
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Re: heater fan non-operational

Post by thebronze »

Knew it 8)
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Amfo
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Re: heater fan non-operational

Post by Amfo »

Hi there-

Got the exact same problem in my car. I have power to the switch. Pulled the little cowl off unther hood over firewall, checked the connections and those are good. Also pulled the battery out to check there as suggested, but what am i looking for behind the battery connection wise?

The switch turns on the AC condenser fan and I put a test light to the connector under the cowl where it plugs in. All three speeds seem to be working?
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Ed Lijewski
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Re: heater fan non-operational

Post by Ed Lijewski »

Most likely the thermal overheat contacts in the blower motor itself are carboned up. Do a search here for "hairdryer" in a post by Mike McCreight re blower motor issues. Blower motor has to come out to repair/fix this. Also, SvoSierra who posts here repairs blower motors.

YMMV ;-)
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Mike McCreight
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Re: heater fan non-operational

Post by Mike McCreight »

Sometimes a good whack will sort them out. Remove the resistor pack, do a "hammer/n/chisel" thing on the motor housing with a long punch or screwdriver. If a motor brush is stuck, that will sometimes free it.
If memory serves, and it sometimes doesn't, the ground is the same as for the wiper motor. If they both quit, it's likely that ground point.
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