Everything new. And still
Thread Starter
Burning Brakes
Joined: Jan 2004
Posts: 769
Likes: 0
From: Ft. Lauderdale Fl
Everything new. And still
Everything new. And still I don't have a high speed fan for my heater and A/C. Only 123 speed. Even the thing with the 3 or 4 springs coils in the engine compartment on the right side. Is there a relay or something I've mist.? 
Le Mans Master
Joined: Aug 2006
Posts: 7,427
Likes: 1,560
From: mount holly NC
2025 c3 ('74-'82) of the Year Finalist - Unmodified
2019 C3 of Year Finalist (appearance mods)
Not sure about your 78 but on my 74 there is a seperate in-line fuse for A/C high speed, it's under the left fender near the master cylinder.
The relay is on the right side on the A/C unit, there are 4 wires:
Black
Yellow
Blue Red hooked it in that order. PG.
The relay is on the right side on the A/C unit, there are 4 wires:
Black
Yellow
Blue Red hooked it in that order. PG.
Thread Starter
Burning Brakes
Joined: Jan 2004
Posts: 769
Likes: 0
From: Ft. Lauderdale Fl
Race Director
Joined: May 2006
Posts: 16,528
Likes: 53
From: Dayton, Ohio
(If you have an early production the rear window defog can knock out high blower if the defog is on.)
Last edited by ...Roger...; Sep 22, 2008 at 08:25 PM.
Thread Starter
Burning Brakes
Joined: Jan 2004
Posts: 769
Likes: 0
From: Ft. Lauderdale Fl
Is the red wire at the relay hot at all times and is the black wire grounded?If so check to see if the orange wire is hot with the blower switch in high position and the key in the on position.Let us know.
(If you have an early production the rear window defog can knock out high blower if the defog is on.)
(If you have an early production the rear window defog can knock out high blower if the defog is on.)
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
If your fan electric system is the same as early '70s cars, the 30 amp 'glass' fuse (bayonet mount) is located on the inner-left front fender just inside the brake master cylinder. It has a red wire coming in and an orange wire going out. It is likely bad.
Drifting
Joined: May 2008
Posts: 1,462
Likes: 43
From: Choctaw Country
All right guys you get to laugh at me on one but hopefully this will help our guy......when I went through my car this past spring I put in a new switch as well, and then didn't have high fan.
Well after lots of checking I took the console back apart and checked the plug in to the switch and low and behold I was slightly off and had missed a prong on the swith so that at first glance the plastic plug into the switch looked good, but on closer inspection you could see where I had missed the prong on reassembly.
Just a suggestion but it might help....
Well after lots of checking I took the console back apart and checked the plug in to the switch and low and behold I was slightly off and had missed a prong on the swith so that at first glance the plastic plug into the switch looked good, but on closer inspection you could see where I had missed the prong on reassembly.
Just a suggestion but it might help....
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