So, waking up one morning and my blower is not working, on any speed.

Checked fuse. I doubt the resistor pack has gone completely bad.

Before I start tearing things apart, what is the most likely cause? Fan control or motor? Was working fine the evening before.

 

Swap in the horn relay

 

Does defrost fire up the blower? This bypasses the resistor pack and points towards a bad motor if it doesnt work either.

 

I am assuming that on the defrost setting the relay is still involved?

 

It’s the defrost relay, so the normal blower relay is also bypassed.

 

The blower will work on the highest speed even with the resistor pack unplugged. It will also work in DEF without the resistor pack. It does require the fuse for all modes. To check the fuse - don't visually check - always electrically check. Replacing a fuse is not sufficient - always check electrically. The fuse input is the top connection on 1985 and later cars, output on the bottom. For pre 1985 cars the fuse input is on the bottom and output on the top. Easiest to check fuse condition with a continuity tester (out of the panel) - but given aging issues with fuse holders and known problems with early panels - check the voltage gets all the way to the fuse output terminal connection too (on the panel) on early models. For 85+ you can test on the fuse - look for the little open dimples on the visible face, check for voltage when active on the lower probe point.

If the fuse is good - then either the head unit/connections or the motor is bad. See if you can feel the DEF relay switching while selecting - if yes - its likely the motor, if no its likely the head unit. You can always test the motor direct in place - pull apart the motor connector and apply 12V to the motor Red=12V batt, Brown=ground (use a fuse in the supply - the motor takes a lot of current so it will likely spark on connection - too easy to short).

Alan

 

Scott I find it odd that you sleep with your blower,
and that you expect it to work when you get up.
I suggest you use some salve on the relays and the fuses.
This will stimulate future operation.

 

If you need one, I've got a plethora of used functional blower motors, left over from custom A/C upgrades....

 

Guys,

Thanks for the helpful inputs. Especially....

This should be all I need to get it going. Now, all I have to do is make the 14,000 trek to get back to the car.

Cheers