Check For Intermittent Problems

CHECK FOR INTERMITTENT PROBLEMS

HINT: A momentary interruption (open circuit) in the connectors and/ or wire harness between the sensors and ECUs can be detected in the ECU data monitor function of the hand-held tester.




a. Turn the ignition switch OFF and connect the hand-held tester to the DLC3.
b. Turn the ignition switch ON. Follow the on-screen directions on the hand-held tester to display the DATA LIST and select areas where momentary interruption should be monitored.

HINT: A momentary interruption (open circuit) cannot be detected for 3 seconds after the ignition switch is turned ON (initial check).









HINT:
- If the hand-held tester's status remains open, check the resistance between the ECU and the sensors, or between ECUs.
- The OPEN display on the hand-held tester remains on for 1 second after the harness signal changes from momentary interruption (open circuit) to normal condition.

c. While observing the screen, gently jiggle the connector or wire harness between the ECU and sensors, or between ECUs.

Result: OPEN display does not change.






HINT: The connector and/or wire harness will be in momentary interruption (open circuit) if the chart fluctuates. Repair or replace connector and/or wire harness as one of them is faulty.