Diagnostic Procedure

DIAGNOSTIC PROCEDURE

1. Check voltage of terminals VF1 and VF2.
- If voltage continues at 0.0 volts proceed to step 2.
- If voltage continues at 5.0 volts proceed to step 7.
2. Check voltage of terminals OX1 and OX2.
- If OK proceed to step 7.
- If not OK proceed to step 3.
3. Check for open and short in harness and connector.
- If OK proceed to step 4.
- If not OK repair or replace harness or connector.
4. Check each item found to be a possible cause of problem.
- If OK proceed to step 5.
- If not OK repair or replace.
5. Check compression.
- If OK proceed to step 6.
- If not OK repair or replace.
6. Does malfunction disappear when a good Oxygen Sensor is installed ?
- If YES replace Oxygen Sensor.
- If NO check and replace Engine Control Module.
7. Check each item found to be a possible cause of problem.
- If OK proceed to step 8.
- If not OK repair or replace.
8. Check compression.
- If OK proceed to step 9.
- If not OK repair or replace.
9. Does malfunction disappear when a good Oxygen Sensor is installed?
- If YES replace Oxygen Sensor.
- If NO check and replace Engine Control Module.