Preparation For Testing

NOTE: If vehicle will not start, see NO START TEST under NON-CODE TESTS in this article.

1) Check vacuum hoses for leaks, cracks, or improper routing. Repair or replace as necessary. Check oil and coolant level. Check electrical connections.

2) Repair any frayed or broken wires. Ensure that all connections are clean and tight. Turn all accessories off. Place transmission in Neutral and set parking brake.

3) Warm engine to normal operating temperature. If air cleaner must be moved, leave all vacuum hoses attached. Remove PCV valve from valve cover.

4) Turn ignition off. Locate self-test connector (on left fender panel, near MCU) and insert a jumper wire between Ground and Self-Test Trigger terminal.

5) Connect the positive lead of a analog volt/ohmmeter to vehicle battery positive terminal. Connect negative lead to Self-Test Output terminal. See Fig 1 . Set voltmeter on 0-20 volt scale. Battery voltage may be shown.

Fig 1: Connections for Function Tests

Courtesy of FORD MOTOR CO.

NOTE: Service codes are shown by voltage pulses or needle sweeps. The first digit is indicated by a series of pulses. The voltage will drop to zero for 2 seconds, then the second digit of the code is displayed. After all service codes are displayed, the throttle kicker will retract.