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So the fan/motor in my heater core is not working. I’m not sure if I need to replace the fan and motor itself or if my resistor is the issue. Though the resistor in the car looks pretty cruddy. But I can’t find a resistor like this one below which as far as I can tell is what my car has. Wallothnesch doesn’t have any available and I can only find the later model ones online. Any advice on what to do or any help finding this part is greatly appreciated.




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What do you mean when you say the motor is not working?

The early cars had a 2-speed blower.  Off, Low and High.

Did you connect 12V directly to the Red wire on the motor and ground to the Brown wire?

Should spin the motor at full speed. If not, lube the fan bearing and try again.

A common problem with the later (3-speed) blower is the female connection on the resistor board. These tend to crack or break.

If yours did, snip off the curved edges of the female connector and turn it into a male (circumcision?). Then crimp a female connector to the power wire.  Easy to check the resistance across the two male tabs on the resistor board. Should be 2.5 Ohms.

Note: The resistor is on the Ground side of the motor circuit.

Here's a sketch of the heater circuit for a later model 3-speed motor but should be very similar to your 2-speed.






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The resistor is unlikely to be the problem because it's just a piece of high resistance wire wound in a coil shape.  It's marked 2.5 ohms in the picture, so If you can get a multimeter it's easily tested.  Broken terminals, the heater fan switch contacts, or frayed wires could also be a problem.  You can also start by just feeding 12V to the motor to see if it turns at full speed.  Polarity matters, running motors with brushes backwards can be bad.  If it turns out to be the resistor,  the later resistor unit with two resistors can be used instead by using which ever resistor's close to 2.5 ohms (or both in series, I forget the exact scheme that's used to get 3 speeds).  Most likely is that you'll find the resistor itself is working fine.  Cleaning it with soapy water, alcohol, orange cleaner, whatever other household cleaners you have will not damage it- the phenolic base is very resistant to solvents.  Cleaning the contacts with abrasion will also be in order- a brass brush or fine emory paper and a light touch, will do the trick.


There are various postings about replacing the fan with other non- 2002 fan motors in the FAQ IF the fan's the problem, including the modern SPAL motorcycle oil cooler fan that is working great in my car (not my idea, someone else posted it)

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4 minutes ago, John76 said:

The early cars had a 2-speed blower.  Off, Low and High.

By "early cars" John means (at least for US spec 2002s) those with VINs below 1664761.  


I'd suspect the motor before the resistor pack, as on high speed, the resistor is bypassed on both two and three speed fans.  An easy test is to connect a voltmeter directly to the + lead wire at the motor itself, and turn the fan on at high speed to see if you're getting 12 volts at the fan.  


I did a column on testing the blower fan motor in place without having to remove it.  PM me if you'd like a copy.



'69 Nevada sunroof-Wolfgang-bought new
'73 Sahara sunroof-Ludwig-since '78
'91 Brillantrot 318is sunroof-Georg Friederich 
Fiat Topolini (Benito & Luigi), Renault 4CVs (Anatole, Lucky Pierre, Brigette) & Kermit, the Bugeye Sprite

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