BLOWER MOTOR WORKS ON ALL SPEEDS BUT HIGH

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echo7bravo

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Anyone know what would cause blower motor not to work in only one of the speeds? Woudn't care half as much if mother nature would leave the south east alone.
 

Rusty Nail

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I know ! I know!

Hi speed is the fuse holder on the firewall above your distributor.
I changed mine to a modern spade type holder because ye olde glass holder 'twas broken and the hi speed was therefore INOP.

The thread is found under "interior" / Heat and AC
 
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chengny

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There probably won't be a fuse in the lead that runs from the junction block on the firewall to the blower relay - not on a 1986 C60 AC system. If there is power at the FW JB, the blower relay is more likely to be the problem:

1975:

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Snoots

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High speed relay is shot.
 

Dougnsalem

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There probably won't be a fuse in the lead that runs from the junction block on the firewall to the blower relay - not on a 1986 C60 AC system. If there is power at the FW JB, the blower relay is more likely to be the problem:

High speed relay is shot.

Could also be the "high" position of the switch being bad, right? Or possibly a wire, but I doubt that....

OK EVERYONE! PLACE YOUR WAGERS!!!

I'm gonna guess switch.... Lol
 

smoothandlow84

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I dunno, I have an 87, replaced the switch, relay, blower motor...and still no high speed. I ended up bypassing the circuit and installed a seperate switch and mounted it in the ash tray. I have high speed now when the alternate switch is on and other speeds with the oem dash switch.
 

Dougnsalem

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I dunno, I have an 87, replaced the switch, relay, blower motor...and still no high speed. I ended up bypassing the circuit and installed a seperate switch and mounted it in the ash tray. I have high speed now when the alternate switch is on and other speeds with the oem dash switch.
So you wanna guess a bad wire? Lol

Man, we could have some fun with this....
 

Snoots

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Could also be the "high" position of the switch being bad, right? Or possibly a wire, but I doubt that....

OK EVERYONE! PLACE YOUR WAGERS!!!

I'm gonna guess switch.... Lol


If you turn the ignition on (engine not running) and turn the switch back and forth between MED and HI you should hear the relay click. If you don't then it's likely the switch. It can be taken apart and the contacts cleaned. If you do hear it click the check the 12V feed to the relay. If that is good, take the relay apart and clean the contacts.

$1 on the relay.
 

Dougnsalem

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If you turn the ignition on (engine not running) and turn the switch back and forth between MED and HI you should hear the relay click. If you don't then it's likely the switch. It can be taken apart and the contacts cleaned. If you do hear it click the check the 12V feed to the relay. If that is good, take the relay apart and clean the contacts.

$1 on the relay.

A dollar???

Ima gonna havta fold. Too rich for me...

Well.... On second thought- put me in for a dollar too. I'll go for the switch. Anyone else?
 

Snoots

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A dollar???

Ima gonna havta fold. Too rich for me...

Well.... On second thought- put me in for a dollar too. I'll go for the switch. Anyone else?

I was going to get it from my wifes' purse anyway.
 

Dougnsalem

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I was going to get it from my wifes' purse anyway.
Lol. I know that feeling from when I was married. I didn't have any money either. Kinda like Al Bundy...
 

1987 GMC Jimmy

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Lol. I know that feeling from when I was married. I didn't have any money either. Kinda like Al Bundy...

He had a pretty hot wife. I don't know how much that would help being broke, and I don't think he cared too much about what she looked like, but I wouldn't be totally miserable.

I'm gonna guess the blower relay on this one. I've had the switch fail where it would be hot even when switched off, and the compressor clutch would engage as soon as you turned the key. The replacement of it with a good spare cured that problem.
 

smoothandlow84

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Everytime somebody asks about hi speed it turns into a huge thread.
And @chengny always tells everybody what time it is..
:emotions34:
I went through the entire checklist that chenghy submitted...and still no high speed....none...so I went another route and obtained high speed
 

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