Initial Inspection and Diagnostic Overview

Inspection and Verification

Correct test results for the Quick Test are dependent on the proper operation of related non-IVSC component systems. It may be necessary to correct concerns in these areas before the IVSC will pass the Quick Test.

Before hooking up any equipment to diagnose the IVSC system, make the following checks:

1. Verity customer's concern(s).

2. Check all engine vacuum hoses for:

- Leaks or pinched hoses: speed control servo to speed control dump valve and speed control servo to manifold vacuum.

3. Check the IVSC and EEC system wiring harness electrical connections for:

- Proper connections

- Loose or detached connectors, wires and terminals

- Corrosion

- Proper routing of harness

It may be necessary to disconnect or disassemble the connector assembly to perform some of the inspections. (Note the location of each pin before disassembly.)

4. Check the powertrain control module (PCM) and IVSC sensors and actuators for physical damage.

5. Perform all safety steps required to start and run operation vehicle tests.

6. Apply the emergency brake. Place the shift lever in NEUTRAL.

7. Turn off all electrical loads such as the radio, lamps, air conditioner, etc. Make sure doors are closed whenever readings are made.

8. Verify engine coolant is at the specified level.

9. Start the engine and let idle until the upper radiator hose is hot and pressurized and the throttle is off fast idle.

10. Turn the ignition switch to OFF.

11. Service items as required, and go to Symptom Chart. Symptom Related Diagnostic Procedures