2nd Gen Non-Engine/Transmission 3 of 4 speeds out on blower motor

[DBartoli]

The three lowest speeds of my 4 speed blower motor went out. The top speed still works. I was using the third speed and it quit just like I shut it off. I have checked the fuse and the relay both are OK.

If anyone has a suggestion I would like to hear it. I don't want to have to pull the dash apart for lack of a better place to start.

DBartoli

 

[BigEasy]

you need a new resistor... top speed worrks on full voltage, all the rest are reduced. fairly cheap and easy fix...

 

[rrausch]

On mine, I can see the resistor by lying on my back in the pass. footwell. Taking the glove compartment door off really helps to get to it.

 

[Lightman]

There's a good chance that if your resistor is out your blower motor caused it because it is worn and drawing more amperage then it should be. It could also be the switch.

 

[DBartoli]

Thanks Big easy,

NRA Endowment Member & High Power competitor

 

[Neibe]

You might want to check the vacuum lines to the switch. My truck fan wouldn't go into high speed the vacuum line had come off way up behind the glove box.

 

[ntillm01]

Ditto on the resistor. Just diagnosed that very thing on my neighbor's Dakota. On that one, the ohm-meter showed which resistor was open (medium 2), which broke the circuit for all of them. When I got it out, it didn't look like any resistor I had seen before. It was a simple, black flat square mounted on the connector. Couldn't see anything wrong with it at all.

 

[TRCM]

And here's a side note... ... . if you EVER get the chance, make sure the plenum/airbox for your heater is free of leaves and debris.



That same resistor is used on the older trucks, and on the older ones, it is in the airflow to the heater core. I had a truck catch fire because I was running the fan on low speed (resistor gets hottest on that speed), and some leaves got in contact with it and caught fire. It wasn't long before the plastic heater box was burning too.



Because of this, I remind everyone on the old dodge truck site I moderate to check this out every year before they start using the heater. Yeah, the resistor is still used in the summer,but the air flowing thru the box is cooler, since the resistor is after the a/c evaporator.



Just a heads up... I'm not sure if the resistor is can do the same thing on the newer trucks (it may be located outside the airflow), but if it can, might be worth some checking into.



#ad




I know you don't want this to happen to your truck !!!!

 

[ntillm01]

My WORD! TRCM, I've got a Power Wagon of that vintage. The resistors today look way different, but they are still in the airbox airflow. But no matter what a resistor looks like, it still has to dissapate heat, meaning that could happen to any airbox with leave in it.



Thanks for the tip!

 

[BigEasy]

WOW!! My question is, "how did the leaves, etc. get in there?" Isn't there a screen on the heater intake?