Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
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 intelligent tester (with CAN VIM).
- Turn the ignition switch OFF and connect the intelligent tester (with CAN VIM) to the DLC3.
- Turn the ignition switch ON. Follow the on-screen directions on the intelligent 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).
DIAGNOSTIC NOTE CHARTItem Momentary Interruption Range (Display) Normal Condition Diagnostic Note SPD SEN FR Front speed sensor RH open detection / OPEN or NORMAL OPEN: Momentary interruption - SPD SEN FL Front speed sensor LH open detection / OPEN or NORMAL OPEN: Momentary interruption - SPD SEN RR Rear speed sensor RH open detection / OPEN or NORMAL OPEN: Momentary interruption - SPD SEN RL Rear speed sensor LH open detection / OPEN or NORMAL OPEN: Momentary interruption - YAWRATE SEN Yaw rate sensor open detection / OPEN or NORMAL OPEN: Momentary interruption - DECELE SEN G sensor open detection / OPEN or NORMAL OPEN: Momentary interruption - STEERING SEN Steering sensor open detection / OPEN or NORMAL OPEN: Momentary interruption - M/C SEN 1 Master cylinder pressure sensor 1 open detection / OPEN or NORMAL OPEN: Momentary interruption - EFI COM EFI communication open detection / OPEN or NORMAL OPEN: Momentary interruption - HINT:
- If the intelligent tester's status remains open, check the resistance between the ECU and the sensors, or between ECUs.
- The OPEN display on the intelligent tester remains on for 1 second after the harness signal changes from momentary interruption (open circuit) to the normal condition.
- 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 has momentary interruption (open circuit) if the display fluctuates. Repair or replace the connector and / or wire harness as one of them is faulty.
Use the Manual With the Right Hardware
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
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