Idle Speed/Throttle Actuator - Electronic: Testing and Inspection

Idle Speed Control (ISC) Servo:

Idle Speed Control (ISC) Servo Location:

To test the Idle Speed Control (ISC) Servo, located on the throttle body, proceed as follows.

1. Disconnect the ISC motor connector.

ISC Servo Continuity Test Hook-up:

2. Check the continuity of the ISC motor coil between terminals 1 and 4.
Terminal 1: ISC motor (retraction)
Terminal 4: ISC motor (extension)

Standard Value...5-36 ohm (@20°C/68°F)

ISC Servo Operational Test Hook-up:

3. Connect 6V DC (four dry cells) between terminal 1 and terminal 4 of the ISC motor connector, and check to be sure that the ISC servo operates.

CAUTION: Apply only a 6V DC or lower voltage. Application of higher voltage could cause locking of the servo gears.

4. If the servo does not operate, replace it as an assembly.