2nd Gen Non-Engine/Transmission changed resistor block--now no fan at all

[MCharlebois]

did not have high on the fan ,changed out the old one ---now i have nothing

tryeed the old one and nothing also... no blown fuses ... . any ideas

thanks marcel

 

[Dave M]

did not have high on the fan ,changed out the old one ---now i have nothing

tryeed the old one and nothing also... no blown fuses ... . any ideas

thanks marcel

On high the resister block is not used but is bypassed. If high doesn't work and other speeds do then the resiter block is not used but not sure which connections when on high at the resister block or fan gives the 12v for high speed to the fan blower. The resisters just lower the voltage for each speed. The resister block is only used on medium and low.



Check fuses... I don't know which one right now. If fuses are good then get your voltmeter and check voltages at the fan connector/resister block. You could remove the fan and jumper 12v and gnd to it to verify the fan is working(Thats what I did)... ... you probably need schematics to figure the pins involved. Mine did not work in vehicle but worked on bench and when I put it together it started working again... ... this has happened several times and I haven't figured out why yet.



Its either the fan, connections at the resister block,fuse or dash fan switch.



Dave

 

[litespeed]

Its either the fan, connections at the resister block,fuse or dash fan switch.

Dave

+1

Check your connections first. Especially since you have already been working on it. Then the fuses, then the fan switch on the dash. The fan switch are known to melt and go bad. It will be obvious if it is bad.

If the fan was working on the first 3 speeds... The resistor is good. Is the fan motor in good shape? A bad motor will fry the resistor.

 

[GAmes]

I had a fan motor quit. A swift kick got it spinning again. Had to do it three or four times on different days to get home. I got a replacement at a u-pull-it yard near here for $10. It was out of a 1500. The resistor block was a couple bucks more so I have one as a spare.

 

[RSimmons]

I had a 3rd gen that had no ac/heat blower also..... Problem was the ignition switch in the steering column. Everything else worked great, took me a little bit to find this one.

 

[MCharlebois]

heard a ccrreeeaaakkk when i started the truck and now it works on all speeds... . thanks for the replies

 

[GAmes]

More than likely it won't work thru the winter, it sounds like the motor is dying. Get a new one before you are without a defroster in a snowstorm going west into Portland, Or. hauling a 35 ft. trailer. I didn't try the swift kick until I had sucked a bunch of button holes out of my seat cover. :-laf