1969 Charger SE with A/C Cant find resistor

4spEd · Jan 18, 2015

Sorting a car I recently acquired. The blower motor seems to work on Hi. Slow doesn't seem correct. The motor does turn slow when ignition is in the on position and no matter what I do the only change on the speed control it is full on or the slow which I think was 5 volts. I cannot get it to turn off. I am trying to find the blower motor resistor, but its nowhere to be found. BTW I did look for loose wires on the switch. Also what voltage will the blower motor get while on low? Any help appreciated.

Sixpactogo · Jan 18, 2015

It is located on the left side of the left defroster outlet. It sounds like yours may have failed or is not connected. I see there is a used one on Ebay. I don't know what the resistance is supposed to be but I have seen some new ones go for over $100.00. Not sure if anyone is rebuilding them but here is a pic of the location on the heater box.

4spEd · Jan 18, 2015

I found it over there hiding behind the hose. It seems fine. I did find a slightly melted connector. I think I also have an intermittent connection at the speed switch. Does anyone know if new switches come with the wires and connector?

Sixpactogo · Jan 19, 2015

I'd say you found part of the problem. Put a new connector on that wire and find a good plastic part to replace the melted one. When I say you found part of your problem, I mean, you need to check out your blower motor. That is what I believe caused the over heating of the connector. Probably at the switch also. When the motor gets tired and dirty, it takes much more current to run it. That is what causes the overcurrent at the switch and resistor. Running a tired blower motor on high is what overheats the connectors.
You may have burned the switch also as that is what usually fails first.
I think I may have a good used switch with the short harness and plug.

4spEd · Jan 19, 2015

Any idea what the current of a good or bad motor on high would be?

Sixpactogo · Jan 20, 2015

I do not know what the amps would be but if I were you with the evidence you have of melted connectors, I would pull the blower motor and have a shop clean and function test it. Since it is pushing 50, I'm sure it needs it.

4spEd · Jan 22, 2015

I bought a new one i will test new against lod and post results.

Dennis H · Jan 22, 2015

Classic Auto Air in Tampa is a good source of factory ac parts and information. fyi.

The Horvaths · Feb 1, 2015

When testing new/old blower motors for current draw, load them the same to get a real comparison. In other words, if the squirrel cage is attached and in ducting, the motors' current draws will be different (higher) that simply spinning an empty shaft. To compare "apples to apples," they should be tested under identical conditions. Either loaded, unloaded, or (cool scientific approach alert!) under both free-wheeling and pushing air at various speeds. Yes, I'm an engineering geek. Heck, some of my favorite toys are vacuum tubes.

4spEd · Feb 8, 2015

Bought a replacement motor, from rockauto. Its junk , really noisy. Any recomendations where to buy a new one?

Sixpactogo · Feb 9, 2015

They show up on Ebay once in a while. I have a used one that I had cleaned and re conditioned for my car then bought a new one. I planned on selling it at a swap meet later this year. If you want it, I need $40.00 plus the ride. PM me if interested. On another note, you could have yours rebuilt for about the same money.

4spEd · Mar 13, 2015

So i went to replace fan and everything i was reading suggested you must remove the heater box from car to separate the fan motor and wheel. Fortunatly somewhere on FBB or FAB i found a suggestion to use heat gun to heat the end of shaft and the plastic blower wheel, it worked perfectly. Thanks to whoevers original idea it was.

1969 Charger SE with A/C Cant find resistor

4spEd

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