Chart 6C-6 Idle Speed Control (ISC) Check

Diagnostic Chart:

ISC Motor Circuit:

CIRCUIT DESCRIPTION
The Idle Speed Control (ISC) Control Check verifies proper ISC motor operation and checks ISC plunger adjustment. This diagnostic procedure requires ISC adjusting wrench J29607.

NOTES ON FAULT TREE
1. This procedure checks for a high minimum air idle which could cause a high idle at closed throttle. It is OK if engine cannot stay running at minimum air idle.

2. Follow Powertrain Control Module (PCM) Trouble Code P030 diagnosis to identify the cause of a faulty ISC motor.

3. This procedure determines ISC authority. This is determined by comparing the minimum Throttle Position (TP) sensor value (with the ISC plunger retracted) to the maximum TP sensor value (with the ISC plunger extended). ISC authority should he adjusted to 10 degrees to 11 degrees of throttle angle.

4. The Idle Learn procedure must be performed after ISC plunger adjustment.