Front HVAC blower motor intermittent

[02Lightning]

I replaced my blower motor resistor, none of the wires look to have been hot. But the blower will stop for no reason, then start back up? The resistor didn't fix anything.

 

[Joseph Garcia]

My thought is that you have an issue with the blower motor. Is it possible that the motor is overheating and has an internal overload shutoff? Or, perhaps, the motor heats up with use and there is a failing winding that becomes disconnected with the heat expansion.

 

[Doubeleive]

I replaced my blower motor resistor, none of the wires look to have been hot. But the blower will stop for no reason, then start back up? The resistor didn't fix anything.

sometimes the motor can burn up the harness connector, the only way to tell is either unplug the blower motor harness and look at the tip with a flashlight or pull the blower motor out and look inside the connector and/or bench test. Had to replace mine it just stopped working because the connector was toast. replaced the plastic piece of the harness and grabbed a used motor out of the junkyard.
pulling the blower motor is easy. one screw and a locking tab to lift up and then it twist's out of its slot and comes down, hard to see up there use a flashlight to see what I am talking about.
NOTE: that there are 2 different versions of the blower motor, the early version prob 07-09 has a slot to get "air" cooled from the hvac box, and the later rmodels do not have the slot and are "self cooled" from the blower motor.
when you pull the motor you will either see a slot with a hole or not.

 

[02Lightning]

I'll look into the blower motor, thanks guys.

 

[Dustin Jackson]

@02Lightning I had a similar problem recently and I thought it was the resistor because when I smacked it the motor would come back on. It turned out to be the blower motor

 

[02Lightning]

I replaced the blower motor, we will see if that helps

 

[02Lightning]

Blower motor did not fix the problem, any other ideas?

 

[Doubeleive]

Blower motor did not fix the problem, any other ideas?

Blower motor resistor although I have not heard of any going out on this gen since they are considerably more beefy than they used to be on the gmt800's, however I have a spare I bought sitting in my tool box just in case, it's been sitting there for probably 4-5 years now.
yours would be the first I have seen, you might want to pull it out and see if it looks melted or anything they do have a big heatsink on them

 

[02Lightning]

Blower motor resistor although I have not heard of any going out on this gen since they are considerably more beefy than they used to be on the gmt800's, however I have a spare I bought sitting in my tool box just in case, it's been sitting there for probably 4-5 years now.
yours would be the first I have seen, you might want to pull it out and see if it looks melted or anything they do have a big heatsink on them

Well, I've replaced the resister and the motor and I still have the problem. No wires or plugs melted anywhere.

 

[Doubeleive]

Well, I've replaced the resister and the motor and I still have the problem. No wires or plugs melted anywhere.

well then that leaves either the controller or possibly a fuse is being wierd as joseph noted above with a possible motor issue, try new fuses first.
do you have a scanner? like a tech2?
is yours the manual control with big knobs or is it the digital auto control?
with the manual control I think it would be hard to tell if the whole unit is just loosing power, with the digital it has lights