v8440

Hi all,

The blower fan in my '98 ram only works on the high setting. I checked both fuses (the one in the dashboard and the one under the hood) with a VOM meter, and both are good. I tried substituting the blower fan relay for another relay with the same part numbers printed on it, and it still only works on high. What should I look at now?

99 cummins

Just found my problem to, in between the fan and the center hump mounted to the bottom of the dash you will find a small plug. Unplug that and pull the two screws out of the plate, when you do a small ceramic block will pull out probably in chunks, thats what needs to be replaced. Gotta play twister to get to it.

v8440

Oh, that must be the resistor that provides the lower speeds.

v8440

Well, I pulled the resistor out, and it looks fine. It's not cracked or scorched. It could still be bad, and I can test it with my meter if I can get a pinout diagram of it and what the resistance values should be. Anybody got a diagram for it?

SilverRam01

I just did this same thing.......

It's a relatively simple resistor. On mine, the crossover spring / clip near the base had come apart. I set it back in place, soldered it, reinstalled. Fan works now,.....and I saved about $50.

99 cummins

$50 !!! I payed $13.00 for mine at Orielly's "excuse the spelling".

v8440

I just went to a junkyard and got one. I haven't tried it yet, so I dunno if that's the problem. I'll go outside in a minute and plug it in.

v8440

Ok, that was not the problem. It still only works on high. Now that I have two resistors, I got my VOM and compared the resistance of them. I put the probes on every possible combination of terminals, and got EXACTLY the same resistance reading between the two in every case, down to a tenth of an ohm. So, I think I can safely rule the resistor out. I'm beginning to wonder if the fan switch might be the problem.

99purplecummins

it is normally 33 something.... your just lucky you have a son that works at an autoparts store

Geico266

Same thing happened to me after I changed out the blower motor. I resoldered it and it works fine.

lglamb

that spring clip was open on mine, but I thot it just
went to an unused spade connection.

Guess if I figure out where I put the thing, I'll re-solder
it and see what happens.

Thanks,
Lowell