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Old 03-18-2012, 06:18 PM   #36
alexxander.foster
Registered User
 
Join Date: May 2008
Location: San Francisco, CA
Posts: 171
My Ride: 2000 323i
Hey guys, just wanted to make an entry to this thread for future reference.

Cyberkaa mentioned that there were two types of pedal control modules (PWG): one with a potentiometer and one with a hall-effect rotary angle sensor. I was able to confirm this but there's almost no information on which part number corresponds to which type of sensor.

After some thinking I realized there's a fundamental difference between the two sensor types that make them easy to identify:
- The potentiometer is a physical connection (i.e., theres a contact that slides along a resistor to get a signal). It will yield a varying resistance value between the positive lead and the signal lead whenever the pedal is depressed -regardless of a power source being supplied.
- The hall-effect sensor is a magnetic field induced signal (i.e., theres no physical connection between the signal wire and the power source). Therefore it will yield an unchanging resistance value when the pedal is depressed. A 5v power source MUST be applied to get any reading from the signal leads if you have the hall-effect rotary angle sensor style throttle pedal.

Fr3nch had a fantastic idea to use an old 5v DC phone charger as a power source for a bench test, do that if you need to take it out of the car.

notes:
Pin assignments:
Sensor 1
- Positive lead = pin 5
- Signal lead = pin 4
- Negative lead = pin 1

Sensor 2
- Positive lead = pin 3
- Signal lead = pin 6
- Negative lead = pin 2

Accelerator Pedal Module (with hall effect style rotary angle sensor):
PN: 35426786282
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