1990 Blown blower motor?

[sleepercoupe]

I’ve got my 1990 all running like a top and am about to order some suspension pieces but I’d like to drive it a bit. The blower motor does not work at all with any position of any switch.

Fuse #9 30amp checked and ok
Blower resistor plugged in and visual looks to not crispy.
Orange and black two wire connector towards firewall has 12v with fan speed switch in any speed which seems odd that’s it’s not varied through the resistor.

Does the front of the hvac assembly come off to access the motor behind the glove box?

Thanks in advance. Ready to really drive it and decide what to do with it. Pretty quick!

 

[Devin]

Can you get to the blower with the glove box down?

 

[zoomlater]

here is an old post, car looks great

Blower Motor Quit

I have had blower motor problems in the past, but they always had a high fan speed setting left in them when the blower control module crapped out. Is there any easy way to figure out what is wrong when the motor does not even turn on? It is really bad weather and pretty cold, so it would be...

shoforum.com

Heat but no blower motor

Did a search and didn't seem to find anything that's pertinant to my problem. Brief history with current problem. Alternator went, replaced Alt and Battery. AC stopped working at end of summer. Plug did not slip out of AC. Other than checking that I never tried to troubleshoot but set on 60...

shoforum.com

 

[SHOrod]

Your SHO has Electronic Automatic Climate Control, correct, or just the knobs? If EATC you'll have a solid state blower motor speed controller, not a resistor per se, and a bad solid state motor controller would prevent the blower from working in any speed. If you have the **** climate control and an actual resistor, then you should at least still have high speed if the blower motor is working since High speed bypasses the blower motor resistor. I should also add that if you're using a digital multi-meter (DMM) they have a very high impedance input so if there is resistance in the circuit due to a melted or bad connection, your DMM may not make that obvious and may still read what appears to be battery voltage.

The blower motor speed control actually only effects the ground for the blower motor. The battery power via fuse 9 is straight to the blower motor on the Orange wire. That's why you're still measuring 12V to the blower motor, assuming you're using a known good ground rather than the Orange/Red wire feed to the motor from the resistor. I should caveat that I am looking at a wiring diagram for a 1992 since that's as far back as my factory service manuals go.

Based on your symptoms and description of an actual resistor, my suspicious would be a bad/seized blower motor. Do you have fused jumper wires so that you could attempt to power the blower motor directly?

-Rod

 

[sleepercoupe]

thanks for the replies. It is not the eatc. It is the good old fashioned three **** job. Which also perplexed that it wasn’t working at full speed to bypass the resister.

Ground controlled circuit gotcha I wondered that as well couldn’t whip up a diagram online with ease. I tried a solid dash frame ground and then I think I tried the harness ground. I’m about to go grab it again. I am pretty certain it’s the motor with no high speed.

I am fairly certain, there are a couple not factory crimp wiring but connectors I can see on the harness near the motor. Yay.


Edit fixed it. Just took it apart and lubed up the bearings with penetrating oil.

 

[Devin]

**** **** ****

Hmm, interesting....