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Old 11-03-2013, 12:59 PM   #1
gramps77
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ohoh, relay getting HOT

The blue wire going into the blower motor relay is obviously building some heat. Any idea? All I have is off or HIGH on the selector at the dash now in my factory AC truck.
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Old 11-03-2013, 01:05 PM   #2
tlawre87
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Re: ohoh, relay getting HOT

I'd start by changing out the relay. Check the resistor too.
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Old 11-03-2013, 02:17 PM   #3
gramps77
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Re: ohoh, relay getting HOT

Quote:
Originally Posted by tlawre87 View Post
I'd start by changing out the relay. Check the resistor too.
Where is the resistor located?
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Old 11-05-2013, 12:09 PM   #4
willett
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Re: ohoh, relay getting HOT

On the blower housing. Its probably pooched. It's that thing the wire harness plugs in to that's held in by 2 screws.
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Old 12-04-2013, 11:03 PM   #5
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Re: ohoh, relay getting HOT

So, I now have swapped both the resistor and the relay. I know have very week lower speed and ZERO high speed.
Should I start shooting for voltages? check the ground? What else should I try?
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Old 12-04-2013, 11:08 PM   #6
willett
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Re: ohoh, relay getting HOT

Check your switch


There should be 12v coming into the switch, and 12v leaving the switch on all speeds. The resistor drops the 12v to different voltages for the different speeds.
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Old 12-04-2013, 11:36 PM   #7
gramps77
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Re: ohoh, relay getting HOT

Im starting to think the new switch and bezel I got from LMC is defective. The harness area at the switch is definitely warm to the touch and before I really had any issues, I would have to jiggle the switch around in the high setting to get it to "set" and work.
A little irritated cause now I'll have to pull the dash back out to troubleshoot.
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Old 12-05-2013, 02:50 AM   #8
willett
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Re: ohoh, relay getting HOT

Get used to it. I can't even count how many times my dash has been apart
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Old 12-05-2013, 02:53 AM   #9
mrolds88
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Re: ohoh, relay getting HOT

Go through and check your terminals. The ones in the picture look a little bit crusty. Extra resistance will give you problems too.
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Old 12-08-2013, 12:55 PM   #10
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Re: ohoh, relay getting HOT

Are there new wire harnesses available anywhere for the A/C and heater system? I'm thinking about just swapping over to a Vintage air kit. The grounds are good now. Im starting to wonder if I got a defective new switch and bezel from LMC, I didnt have any issues until I installed the new one.
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