Heater Fan Resistor Pack

[Gonzo]

Blower motor resistor looks fine, still only works on high.

I have that problem where the blower only works on high. I checked the resistor, and the connections, and all looks good. I even checked the switch on the dash for continuity, but it was good too.

If the resistor looks fine, and all the coils have continuity, could it still be bad? I'm tempted to just go buy a new resistor to see if it works, but I wanted to see if anyone has any ideas.

 

[Peter Westling]

Mine looked fine too, but it was still the problem, ok it was little bit corroded but I couldnt see if it was broken with my eyes. Try measure it for the resistance, Also check the connector, you might go over it with some sandpaper if the connector is corroded.

 

[Gonzo]

I already went over everything with sandpaper, and measured all continuity and resistance. I think I am going to just get a new resistor and hope that is the problem.

 

[gijoecam]

Yes, it could still be bad. There is a thermal limiter on the main power that comes into it. That limiter can fail without any visible sign. Mine did last Thursday. It took me all of an hour to replace it (including the ride up to the dealer to get the new part).

-Joe

 

[Gonzo]

Well, I put a new resistor pack in, and everything works now. I compared the old and new ones, and it turns out it was the thermal limiter that was bad. Thanks for all your help. I'm glad I didn't have to take it into the dealer $$$

 

[shortstack]

do any of you guys have a part number for the resistor pack for like napa, carquest, shucks or something cause i cant seem to find it?

 

[cjones101812]

have you tried the dealer?? it's probably a dealer only part. besides, your first one lasted 8 or 9 years so may as well replace it with an OEM part to get another 8+ years out of it.

 

[tobybul]

97 explorer

I noticed that the fan works only at the highest switch setting. I changed the resistor under the hood but no effect. The resistor I got from NAPA.

Could it be that the NAPA unit is bad? That spot is a real PITA to get to next tot he fan blower. I really don't want to get in there again but looks like I might have to.

I basically went by feel most of the time as I could hardly see the connectors.

 

[cjones101812]

I noticed that the fan works only at the highest switch setting. I changed the resistor under the hood but no effect. The resistor I got from NAPA.

Could it be that the NAPA unit is bad? That spot is a real PITA to get to next tot he fan blower. I really don't want to get in there again but looks like I might have to.

I basically went by feel most of the time as I could hardly see the connectors.

with the blower resistor connector disconnected. key ON, heater ON, fan switch on LOW or MED. jump the O/BK wire to ground (at the connector). does the fan come on??

 

[tobybul]

with the blower resistor connector disconnected. key ON, heater ON, fan switch on LOW or MED. jump the O/BK wire to ground (at the connector). does the fan come on??

I did this about 3 mos ago. To my recollection, it was pretty difficult to reach that spot since a few things were in the way.

But this weekend, I'll give it a shot. Maybe the terminals were corroded.... maybe the original resistor was ok but terminals went bad.....

 

[gijoecam]

Indeed, see post #7 above. If the terminals on the old resistor pack were bad, odds are the connector is no good either.

For more space to work in, remove the cruise control servo and the washer fluid reservoir. It makes it a little easier to get down in there.

-Joe

 

[jnuchter@videotr]

Resister

My blower worked intermittently on all speeds ,and now stopped. Could it be the diode in the pack?

 

[gijoecam]

My blower worked intermittently on all speeds ,and now stopped. Could it be the diode in the pack?

There's no diode there, only a thermal overload, and once it goes, it's dead. The fan should only work on high at that point.

Is it working on high, or are all speeds working intermittently?

 

[jnuchter@videotr]

The blower worked intermittently on all speeds but now stopped completely. No fan whatsoever. When it did work it lasted for vhours on any speed, but now nothing at all.

 

[jnuchter@videotr]

And its really cold in canada!

 

[gijoecam]

You'll need to chase down the problem with a test light or multimeter. Do you have the automatic electronic temperature control, or the three knobs?

-Joe

 

[jnuchter@videotr]

I have the three knobs

 

[Raiden1]

I just purchased a 96 XLT, and the only problem it is having is this. Only off or high on the fan. Should I be looking in the same place in the engine compartment for this resistor pack?

Thanks for any help.

 

[gijoecam]

You need to replace the resistor pack. It'll be on the passenger side of the air box, below/behind the washer fluid and coolant reservoirs. It's easier to get to if you remove the cruise control servo too (one bolt). Also, be sure to check the connector itself. The connector is not weather-tight and tends to corrode with time. This causes a poor connection, which means resistance, and electricity plus resistance equals heat. The connector on mine melted down. I've posted the pics here before, but the link to my gallery is in my signature if you want to see them.

Oh, and the replacement pig-tail should be available from any dealer if you need it. IIRC, it was around $13.

-Joe

 

[winsorcoke]

I have this problem also. Make sure you check the connector well. I can wiggle the wires on mine and all the other speeds come on but won't stay on. I pulled the resister to clean it up, but it's pretty bad. I would suggest that people just go ahead and change both the resistor and harness if you have any corrosion.