Diagnostic Notes

ROAD TEST

Road test vehicle to verify reports of speed control system malfunction. The road test should include attention to the speedometer. Speedometer operation should be smooth and without flutter at all speeds or surging may be caused in the speed control system.


LOGICAL TESTING SEQUENCE

Before starting test procedures, visually inspect speed control system for disconnected vacuum hoses, corrosion on electrical connectors, or proper cable operation. After visual inspection, perform the test procedures using the following guidelines:
1. Always start at Test 1. Starting at any other test may give incorrect results.
2. At the end of each test, reconnect all wires and hoses.
3. Ensure vehicle being tested has a fully charged battery.
4. When checking voltage or continuity at the engine controller 60-way connector, use the terminal side (not wire side) of the connector. Use care when making electrical tests to prevent accidental shorting of terminals, such mistakes can damage fuses or engine controller.
5. Perform the indicated verification test after vehicle repairs have been made.


INOPERATIVE SYSTEM

If road test verifies an inoperative system check and verify the following:
1. Inspect system electrical connections for loose, corrosion or bent terminals.
2. Verify correct installation and condition of vacuum hoses.
3. Check for correct installation of vacuum check valve. End marked VAC must point toward vacuum source.
3. Verify fuse integrity, with test lamp.