Idle/Throttle Speed Control Unit: Testing and Inspection

Switch Test E.7.2:

ISC Circuit:

DISPLAY CONFIGURATION:

After .7.0 is displayed on the Fuel Data Center (FDC), the PCM/ECM switch test can be initiated by depressing the brake pedal when the brake pedal has been depressed the FDC will display E.7.0. AT this time the HI and LO buttons on the Electronic Climate Control (ECC) panel can be used to select the specific switch test. When a specific test has been selected and that switch activated, the display will alternately display the code for that test and E.0.0 to confirm the switch is working.

TEST DESCRIPTION:

This test detects the open and close of the nose switch of the Idle Speed Control (ISC) at terminal A7 of the PCM/ECM.

NOTES ON FAULT TREE:

1. The throttle body must be removed to disconnect the ISC jumper from the ISC. An ohmmeter should be used to inspect the jumper for opens and shorts. The ISC throttle switch can also be checked with an ohmmeter for switch operation.