Idle Speed Motor Position Sensor: Description and Operation
*** UPDATED BY TSB #913017, DATED NOVEMBER 1991The original O.E. service showed an incorrect motor position sensor connector.
Motor Position Sensor Circuit:
The Motor Position Sensor (MPS), located in the Idle Speed Control (ISC) servo, is a variable resistor type sensor. It uses a plunger (contact), that is connected to the ISC servo and a set of electrical windings, that are stationary. As the servo moves, so does the plunger, changing the output Voltage of the sensor. The ECU uses this signal to determine the position of the ISC servo.