Check For Intermittent Problems [10/2017 - 10/2020]
WARNING: This page is about a different car, the 2020 Lexus LS 500h, 2019 Lexus LS 500h, and 2018 Lexus LS 500h. However, it is still accessible from the selected car via links, so may be relevant.
- CHECK FOR INTERMITTENT PROBLEMS
HINT:
A momentary interruption (open circuit) in the connectors and/or wire harnesses between the sensors and ECUs can be detected using the Data List function of the Techstream.
- Turn the power switch off.
- Connect the Techstream to the DLC3.
- Turn the power switch on (IG).
- Turn the Techstream on.
- Follow the directions on the Techstream to display the Data List and select areas where momentary interruptions should be monitored.
HINT:
- A momentary interruption (open circuit) cannot be detected for 3 seconds after the power switch is turned on (IG) (initial check).
- If Error remains displayed for one of the items on the Techstream, check for continuity between the ECU and the item for which Error is displayed.
- If a momentary interruption occurs and Error is displayed on the Techstream, Error will remain displayed on the Techstream for 1 second after the circuit returns to normal.
Chassis > ABS/VSC/TRAC > Data List
Tester Display Measurement Item Range Normal Condition Diagnostic Note FR Speed Open Front speed sensor RH open detection Error or Normal Error: Momentary interruption
Normal: Normal- FL Speed Open Front speed sensor LH open detection Error or Normal Error: Momentary interruption
Normal: Normal- RR Speed Open Rear speed sensor RH open detection Error or Normal Error: Momentary interruption
Normal: Normal- RL Speed Open Rear speed sensor LH open detection Error or Normal Error: Momentary interruption
Normal: Normal- Yaw Rate Open Yaw rate sensor open detection Error or Normal Error: Momentary interruption
Normal: Normal- Deceleration Open Acceleration sensor open detection Error or Normal Error: Momentary interruption
Normal: Normal- Steering Open Steering angle sensor open detection Error or Normal Error: Momentary interruption
Normal: Normal- Master Cylinder Open Master cylinder pressure sensor 1 open detection Error or Normal Error: Momentary interruption
Normal: Normal- Master Cylinder2 Open Master cylinder pressure sensor 2 open detection Error or Normal Error: Momentary interruption
Normal: Normal- Stroke Open Brake pedal stroke sensor assembly open detection Error or Normal Error: Momentary interruption
Normal: Normal- FR Wheel Cylinder Open Front wheel cylinder pressure sensor RH open detection Error or Normal Error: Momentary interruption
Normal: Normal- FL Wheel Cylinder Open Front wheel cylinder pressure sensor LH open detection Error or Normal Error: Momentary interruption
Normal: Normal- RR Wheel Cylinder Open Rear wheel cylinder pressure sensor RH open detection Error or Normal Error: Momentary interruption
Normal: Normal- RL Wheel Cylinder Open Rear wheel cylinder pressure sensor LH open detection Error or Normal Error: Momentary interruption
Normal: Normal- Accumulator Open Accumulator pressure sensor open detection Error or Normal Error: Momentary interruption
Normal: Normal- HV Communication Open Hybrid vehicle communication open detection Error or Normal Error: Momentary interruption
Normal: Normal- Air Bag ECU Communication Open Air bag ECU communication open detection Error or Normal Error: Momentary
interruption
Normal: Normal- - While observing the screen, gently jiggle the connectors or wire harnesses between the ECUs and sensors, or between ECUs.
OK
Normal is displayed.
HINT:
If the display changes, this indicates that there has been a momentary interruption (open circuit) in the connector and/or wire harness. In this case, repair or replace the connectors and/or wire harnesses as one of them is faulty.