Changed Heater Control Resistor Same Prob still

[ccm2001]

Only 1 & 4 work on my dash for the blower. 2 & 3 dont.
I changed the Resistor and still same problem.
Once in a while 2 and 3 will work but rarely.

Any Ideas? Is it the switch i should be looking at

Thanks Ccm. 03 xlt 4.0 sport

 

[koda2000]

Well, the remaining possibilities are:

Switch
Wiring or wiring connector
Blower motor (which seems unlikely)

The switch sends 12v through different resistors on the ballast resistor and that sends various voltages to the motor giving you your 4 speeds.

 

[762mm]

Had the same problem, did the same thing (changed resistor) and the culprit finally turned out to be the switch in the dash. When I pulled it out, it had a microscopic tear in the metal that connects the various positions of the blower. I initially soldered it and it worked for a few weeks, then the solder cracked, lol.

Luckily, a new switch was just a couple of bucks at Rockauto... and it's been working great ever since.

 

[ccm2001]

Thanks alot could you direct me to the part no# on rockauto.

Had the same problem, did the same thing (changed resistor) and the culprit finally turned out to be the switch in the dash. When I pulled it out, it had a microscopic tear in the metal that connects the various positions of the blower. I initially soldered it and it worked for a few weeks, then the solder cracked, lol.

Luckily, a new switch was just a couple of bucks at Rockauto... and it's been working great ever since.

 

[koda2000]

Thanks alot could you direct me to the part no# on rockauto.

Pick one...
http://www.rockauto.com/en/catalog/...,electrical-switch+&+relay,blower+switch,4248

 

[ccm2001]

so i changed the switch just now and still same issue!, wtf can be wrong, i changed the resistor and switch..

any other ideas guys?

 

[david4451]

Change the connector that connects to the blower resistor, if you haven't already. That was my problem caused by corrosion, also first off I changed resistor and connector with Dorman parts and position 1 didn't work, put original resistor in and now all 4 positions good.

 

[429CJ-3X2]

Change the connector that connects to the blower resistor, if you haven't already. That was my problem caused by corrosion, also first off I changed resistor and connector with Dorman parts and position 1 didn't work, put original resistor in and now all 4 positions good.

I just changed the resistor on the blower motor of my Sport Trac last weekend. I did not change the connector, which is available at the parts stores, but wondered if I should have as all the prongs were really rusty. I sprayed it good with Pyroil (rust buster) and put it back together. So far it works fine. As I researched the job here on the forum, I saw people have gone back to the parts store for that connector, so it's obviously a common problem.

FYI- my fan worked only on positions 1 and 4. As rusty as the connector and resistor both were, I don't know how it worked at all.

 

[mic98xlt]

I had a similar problem of 2 blower speeds not working and the first thing I did was to replace the blower resistor. The new resistor only lasted a week and the problem at first appeared corrected before the original 2 speeds problem came back. I then metered and checked dash fan switch, cleaned and checked fan relay under hood, changed wire connector for blower resistor and problem still remained. The final culprit was the blower motor itself (aftermarket) that was binding which caused fan resistor to burn out. I suggest you physically take out the blower motor and make sure the cage is free of debris and it spins freely. Also recheck resistor if blower is found to be binding, which can burn out a brand new resistor quickly once again. My fan motor itself had been binding due to internal bearings which overworked the resistor causing it to overheat and burn out, so I ended up replacing it twice.