psycho dad

hey guys,
I upgraded my blower motor to a C4 in my '76 , but it quit working. I hope its just a fuse, I know motor is okay. Can someone tell me which fuse it is? Fuse box is too hard to reach to pull them all to check.
Also, I may need a new switch. Does the blower have 4 speeds? I have three speeds and nothing when I switch it to high.
Thanks

Peterbuilt

Top right side in the fuse box




The 'high speed' is fused (30) on the ORANGE wire near to 'JUNCTION BOX' on the lower part of the diagram

'75

The high speed has a relay with a separate fuse on my 75 with air.

psycho dad

thanks guys!

Peterbuilt

The 30 amp inline fuse between the red and orange wire runs along the top lip on the left fender, did you find it?

0Willcox Corvette

On your car it is very common for the high blower relay to either fail or for the lead (ORANGE) wire connector going to it to burn (because they are so close to the exhaust manifold). When they get hot, the melt a little and the wire doesn't make good contact.

So... I'd go to the high blower switch mounted on the heater box and check the wires (orange) there first. Your issues points to this as the problem especially considering you still have the other speeds.

Go to the orange wire and check the connector to see if it's burned, put the blower motor in high speed and see if you have power on that wire too... If you do, then I'd pull the relay and... personally I'd take it apart and fix it if possible, if not I'd replace it. The relay has an electromagnet inside and it has points on it that can burn and cause you problems so it's easy to pop the cover off the relay and file the points.... but I still feel that you have an issue with the hot wire going into the relay and/or the connector.

All speeds go through the resistor... except high.... and this is the most common issue.


Willcox

Here is a better pic.

psycho dad

Hey guys,
Sorry I didn't check back to see those last 2 posts. I really do appreciate your help. I've been trying to get things back together in my limited free time.
Yesterday I put my dash panel back in and realized my instrument lights are not working, as well as the blower motor. Everything looks okay in the fuse panel,
I'm wondering if I pulled a ground wire or something. I'm going out tonight to find that fan relay.

psycho dad

I found the relay, but not the inline fuse yet. Until I figure out why there' s no power I can't check them