AC / Blower

[budwisr6]

I recently had my AC system replaced and everything was working correctly until yesterday.
I drove the truck for 10 minutes with the AC on and as usual I shut the AC off before I cut the truck off. When I restarted the truck about 20 minutes later, I went to turn on the AC and nothing. The control panel itself lights up, but nothing blows, you hear nothing at all. I was slightly annoyed, but that's to expect from a 29-year-old truck.

This morning, I was able to lightly hit the blower motor outer casing 3 times and that kicked the blower motor on. So, for the time being the blower motor is working.

My question is, do I need to do any diagnostic work to rule out anything else? My mind set is, if the blower motor now works, I would replace the blower motor and the resistor, and I should be good.

Just an FYI, the control panel for the AC / Heat is the correct unit, it's for a 1995 model, stand-alone year and I replaced the unit when I bought the truck a few years ago. I know that doesn't mean that the control unit isn't bad, but if the unit is lighting up with the AC button pressed in, I think I can eliminate that since when I hit the blower motor it started to work again...

Appreciate any advice and feedback.

 

[east302]

Check with a meter, but if you have power at the blower wire under all fan speeds, then the resistor and blower switch (at the panel) should be fine.

I’d pull the blower and see what it looks like. If it has rust on it, use a mirror and look up into the blower housing intake. There’s screw at the top that attaches the windshield plastic cowl. When it leaks, water gets into the blower housing and can cause issues. Usually your passenger floor is wet as well.

 

[AK49BWL]

Sounds like a textbook bad blower motor to me. I would replace sooner rather than later because the motor will draw excess current if it's stopped when it should be running, and melt the connector to your fan switch in the HVAC control head.

 

[evilunclegrimace]

I would check my power and grounds before I did any thing else. After they are verified good THEN I would jump into further testing.

 

[HotWheelsBurban]

Sounds like a textbook bad blower motor to me. I would replace sooner rather than later because the motor will draw excess current if it's stopped when it should be running, and melt the connector to your fan switch in the HVAC control head.

The blower motor isn't too expensive, I think I paid around $50 for the Murray one I got for my crew cab. It was doing the "I need to be kicked" thing for a while, and since it was still summer ish around Houston, Texas I replaced it. No more kicking required, and it moves more air than the old one did. But the old one, was the original one....
When you replace the blower motor, be sure to note where the ground terminal is, and move it over, and also move over the metal washer tubes from the old motor. These keep the bolts from being overtightened. The new motor won't come with these parts.