Iffy A/C just stopped working when stop?

[Truck Guy99]

Truck is an 05 Chevy Silverado 1500. About 6 months ago the trucks A/C shut off when you turned the fan speed to 5 but would blow very lightly on 0. All fan speeds between worked fine no matter if you were moving or sitting still. This was never an issue so we just dealt with it. Now when you are sitting still it won't blow at all no matter what you turn the knob to. When you start going down the road, it blows but barely. The air is very cold when it does this. We replaced the A/C fuse and the resistor that I'm told is common to fail and neither changed it or even made a difference. Could it be the climate control or is it something else? I'm in the middle of a Texas summer and need A/C!

[95 S_Trucker]

Was the resistor pigtail melted? There are tsbs and recalls on the pigtail and resistor.

The motor could be the problem. It could be the control head.

Does the truck have automatic climate control? Or just standard controls?

[Truck Guy99]

Originally Posted by 95 S_Trucker

Was the resistor pigtail melted? There are tsbs and recalls on the pigtail and resistor.

The motor could be the problem. It could be the control head.

Does the truck have automatic climate control? Or just standard controls?

Resistor pigtail was in great shape. Looked like it may have been replaced before but not sure

I'm assuming standard controls by the looks of it



How do I diagnose if it's the control head or motor?

[95 S_Trucker]

Those are standard controls.

Check for power and ground at the blower motor connector with a multimeter. unplug the blower. using dc volt setting on a meter, carefully back probe or hold the leads up to the blower motor connector. Then turn the key on and go through all the speeds. The voltage should vary, with 5 being close to full battery voltage. If everything is good, replace the motor.

A quick way to test the motor is turn the key on, turn the speed to 5, then give the motor a wap, with a small hammer, a foot, or a fist. If the motor starts to run, replace it.


Is that a 1500HD? I see a trans temp guage

[Truck Guy99]

Originally Posted by 95 S_Trucker

Is that a 1500HD? I see a trans temp guage

No, that's a pic from google images

[Mr-Jack]

same thing happened to me...blower motor resistor melted...I ordered one from amazon and replaced it...my part number for my 02 2500HD 8.1 was a dorman 973-004. takes about 15 minutes to replace...now all speeds work and blows fine.

check the image below

[Truck Guy99]

Ok so I got the issue fixed. It was a bad resistor and the control. The control panel wouldn't light up with the rest of the interior and when it did it was usually dim. This told me was shorted out. But now there is melted wiring on the pigtail of the resister on the truck side. Where can I get a replacement? Its the plug that comes from the dash, not the resistor.

[Mr-Jack]

Originally Posted by Truck Guy99

Ok so I got the issue fixed. It was a bad resistor and the control. The control panel wouldn't light up with the rest of the interior and when it did it was usually dim. This told me was shorted out. But now there is melted wiring on the pigtail of the resister on the truck side. Where can I get a replacement? Its the plug that comes from the dash, not the resistor.

junkyard?

[truckdude239]

gm sells them