1970 Cutlass - 350 Rocket

My A/C fan just stopped working - all fan speeds. I believe because all speeds do not work it is a blown fuse. Where is the blower fuse and relay located?

THanks,
Bill

 

There is an inline fuse holder with a separate 30A fuse for the high speed fan only in the wire that runs along the firewall, and there is a fuse in the fuse block for the low speed fan settings. If you have no fan at all, either both fuses are blown or the problem is something other than the fuses.

 

Will check the 30A inline fuse. The low speed fuse in the fuse box is fine.

Thanks
Bill

 

Just looked under the hood for the 30A inline fuse along the fire wall. Does anyone have a picture of what it looks like?

 

Is this it?

 

I moved your posts to its own thread instead of hijacking one that has nothing to do with your issue.

 

Since the motor doesn’t work on any speed, the blower motor or high blower relay is a likely suspect. Do you have access to a wiring diagram?

 

^^^THIS. The high speed power supply is completely separate from the low speed supply. The only common parts of the circuit are the motor, the wire from the high speed relay to the motor, the relay itself, the motor ground wire (on A/C cars only), the fan speed switch on the faceplate, the internal master switch, and the power to the control head (since this not only operates the low speeds directly but also operates the high speed relay).

The very first test is to see if the blower motor works. Pull the connector off the high speed relay and apply 12V to the purple wire in the connector. If the blower runs, the motor is good. If not, figure out why. Note that A/C cars have a separate ground wire from the motor to the firewall due to the fiberglass HVAC box. Heater-only cars use a metal box and don't need this wire.

 

A wiring diagram would help - thank you.

 

1970 Chassis Service Manual, page 1C-12, figure 1C-20.

 

[QUOTE=wherlehy;1273767]Is this it?

[/QUOTE
Test your hot wire at the blower that’s where I start. Most times it’s just a bad connection.

 

You guys are the best!! With your help and following the wiring schematic it ended up being a loose 50 year old connection.

Thank you all for your help!!

-Bill

 

Thanks!