Diagnostic Procedure

DIAGNOSTIC PROCEDURE

1. CHECK FUEL PUMP OPERATION.
^ If OK proceed to step 2.
^ If not OK proceed to step 3.

2. CHECK FOR OPEN AND SHORT IN HARNESS AND CONNECTOR BETWEEN THE DATA LINK CONNECTOR (DLC1) AND FUEL PUMP ELECTRONIC CONTROL UNIT (ECU).
^ If OK proceed to step 5.
^ If not OK repair or replace harness or connector.

3. CHECK VOLTAGE OF TERMINAL "+B" OF DLC1.
^ If OK proceed to step 4.
^ If not OK check ECM power source circuit.

4. CHECK FOR OPEN AND SHORT IN HARNESS AND CONNECTOR BETWEEN DLC1 AND FUEL PUMP.
^ If OK repair or replace fuel pump.
^ If not OK repair or replace harness or connector.

5. CHECK VOLTAGE OF TERMINAL "FPC".
^ If OK replace fuel pump ECU.
^ If not OK proceed to step 6.

6. CHECK FOR OPEN AND SHORT IN HARNESS AND CONNECTOR BETWEEN ECM AND FUEL PUMP ECU.
^ If OK proceed to step 7.
^ If not OK repair or replace harness or connector.

7. CHECK FOR OPEN AND SHORT IN HARNESS AND CONNECTOR BETWEEN ECM AND FUEL PUMP ECU.
^ If OK check and replace ECM.
^ If not OK repair or replace harness or connector.