Why Blower Doesn't Work on all Speeds? Diagnose & Repair 3rd Gen Camaro Heater - A/C Blower

One of the 4 fan speeds in my Camaro Heater A/C blower doesn't work. It has been bad for a long time and it's time to dig in and find the problem. I need to go through the electrical circuits for the HVAC system switches and resistors.
Intro / Plan 0:03
Check Underhood Wiring and Resistors 2:26
Test Used Replacement Part 12:42
Remove and Check Dash Control Switch 17:31
How Did I Remove the Pins? Inspect the connector and switch 20:04
Wrap up & Test the Repair 23:23
DISCLAIMER: In my videos and written or text comments, I provide demonstrations, suggestions, and opinions on techniques, methods, and materials for various projects. While I try to be accurate, there are no guarantees, expressed or implied, that my information is correct and will work for you. If you wish to use any of this information, you must check and verify that it is appropriate for your use - use it at your risk. Do-it-yourself projects are variable and there are risks in conducting them.

[@AV131082]

Well done Dan, thanks for the video!

[@bitsofwisdom460]

My pleasure!

[@JohnCRV]

You sir, have the patience of Job! Thank you for taking the time to show and explain the whole troubleshooting process. Happy Easter.

[@bitsofwisdom460]

Thank you for your kind comments. Some jobs do require lot of patience. This one wasn't so bad on that front. The videos were I was replacing the bellows on my Mercruiser - that was stretching my patience in a big way. And, Happy Easter to you, too.

[@mikebruegger8654]

Perfect... Man, your lucky I don't live down the street. I'd be there all the time. Mine needs some care in that area too. A metal piece of the slide switch fell on the floor long ago and for a while I didn't know what it went to. I also have to replace the heater core so, that day is coming..... 😊

[@bitsofwisdom460]

I was fortunate to find a good control from a parts car, that helps a lot. I replaced the heater core long ago while the engine was out. I just knew the cooling system was really bad. The radiator had so much corrosion, I wasn't going to take the risk on the heater. I think I used a Spectra aluminum heater core. It's a little tough working the core in and out of the heater box under the dash, but it wasn't too bad.

[@msracingcomponents6550]

Thank you for sharing! 👍

[@Dbomb81]

I have no fans at any speed working. Resistor isnt the issue, replaced the old one, still nothing. Now I've tested my fan speed switch it checks out ok. I'm guessing its not the high speed relay, as none of the speeds work not just the high speed. What should I investigate next?

[@bitsofwisdom460]

Assuming that you have a good power feed from the fuse block to the switch and since everything tests out ok to the resistor, the manual would tell you to check the voltage to the fan motor and grounds. If heater only system, voltage test from orange feed wire to ground should have battery voltage and voltage test from orange wire to black (ground wire) should have battery voltage. If A/C, it's the same except purple wire is feed rather than orange. If both tests pass, fan motor is likely bad. If first test passes and second test fails, then ground connection is bad.