Diagnostic Procedure

WIRING DIAGRAM





DIAGNOSTIC PROCEDURE
1. CHECK VOLTAGE OF VACUUM SWITCHING VALVE (VSV FOR EGR) POWER SOURCE.
^ If OK proceed to step 4.
^ If not OK proceed to step 2.

2. CHECK RESISTANCE OF VSV FOR EGR.
^ If OK proceed to step 3.
^ If not OK replace VSV for EGR.

3. CHECK FOR OPEN AND SHORT IN HARNESS AND CONNECTOR BETWEEN EFI MAIN RELAY AND ECM.
^ If OK check and replace ECM.
^ If not OK repair or replace harness or connector.

4. CHECK EGR SYSTEM.
^ If OK proceed to step 5.
^ If not OK repair EGR system.

5. CHECK RESISTANCE OF EGR GAS TEMPERATURE SENSOR.
^ If OK proceed to step 6.
^ If not OK replace EGR gas temperature sensor.

6. CHECK FOR OPEN IN HARNESS AND CONNECTOR BETWEEN EGR GAS TEMPERATURE SENSOR AND ECM.
^ If OK check and replace ECM.
^ If not OK repair or replace harness or connector.