Heater Fan Speed Problem
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Joined: Mar 1999
Posts: 60
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From: Arlington, VA USA
Heater Fan Speed Problem
Can someone give me some help with how to get the high speed setting to work on my heater fan? The last two positions on the fan switch are the same speed.
Is there a fuse or link somewhere that I can check.
Thanks
Ray
Is there a fuse or link somewhere that I can check.
Thanks
Ray
Le Mans Master
Joined: Jul 1999
Posts: 9,206
Likes: 17
From: Sewell NJ
Re: Heater Fan Speed Problem (Ray B)
Hi Ray
I'm not sure about your car but on my 74 there is an in-line fuse in the engine compartment right under the master cylinder. This fuse controls the high speed blower setting. I'm not sure of the amp rating for the fuse and I'm here at work so I can't check. It should be in the owners manual or repair manual.
I'm not sure about your car but on my 74 there is an in-line fuse in the engine compartment right under the master cylinder. This fuse controls the high speed blower setting. I'm not sure of the amp rating for the fuse and I'm here at work so I can't check. It should be in the owners manual or repair manual.
Burning Brakes
Joined: Apr 2000
Posts: 1,207
Likes: 1
From: Cave Creek AZ
Re: Heater Fan Speed Problem (vettfixr)
If you look just above the fan motor, above where the AC/Heater unit is located you will see a rather good sized oblong plate with a 3 wire plug going to it. That is the fan motor resistor (believe that is the right terminology). It is held in with 2 1/4" nuts. If you pull the resistor you may have one or more of the coils in there burnt off. Give that a try. If not then take a look at the purple wire going into the fan motor itself. If there is a great deal of play where the wire meets the fan motor housing, that could be grounding out there and interfearing with the fan speed. The speed is determined by the amount of resistance the current has to pass through. At High there is no resistance at all the fan gets the full 12v, at medium, and low, the 12v is reduced by adding resistance to the circut causing the motor to turn slower.
Check the resistor,
JoeB
Check the resistor,
JoeB
Racer
Joined: Jan 2001
Posts: 495
Likes: 0
From: ma
Re: Heater Fan Speed Problem (Ray B)
Sounds the like the high speed blower relay has died.its just to the left of the resistorspeed coils[not sure if the name is correct] but the relay supplies full voltage to the blower this is what gives you the highest speed nothing unque about this relay,you can go original or after market on this job :cheers:
Pro
Joined: Jun 2000
Posts: 668
Likes: 1
From: KY
Re: Heater Fan Speed Problem (Paul 75 L82)
had the same thing. replaced the relay, no deal. checked the resistors, they were fine. It was the in-line fuse. On a 76, the wire comes through the firewall between the power brake booster and the distributor. On mine, the fuse holder was tucked up behind the distributor. The fuse holder s one of those plastic things with the tabs. Over the years, the plastic became brittle and just broke. I believe a new holder was about $1.25 and a 25 amp fues (I believe, but check your manual or the fuse that's there). It's one of the glass tube fuses.
It's sure a lot less expensive than starting replacing relays and resistors. Just ask me.
Jeff S.
It's sure a lot less expensive than starting replacing relays and resistors. Just ask me.
Jeff S.
