Date registered: Dec 2005
Vehicle: 222.132 & 221.122 & 212.025 & 906.633
Mentioned: 3 Post(s)
Quoted: 32 Post(s)
The resistor is actually a regulator on cars as new as this one. If you are handy with a multimeter, you can measure the output of the regulator at the input to the actual motor.
How much has it been driven? The motor brushes would wear out but it takes quite a lot of miles, the regulator should be more likely.
You could also bypass the regulator but you would have to be careful, the current to the motor would be pretty high.