Lexus ES: Check For Intermittent Problems
CHECK FOR INTERMITTENT PROBLEMS
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.
(a) Turn the power switch off.
(b) Connect the Techstream to the DLC3.
(c) Turn the power switch on (IG).
(d) Turn the Techstream on.
(e) 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.
| 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 | - |
| Stroke Open | Brake pedal stroke sensor open detection | Error or Normal | Error: Momentary interruption Normal: Normal | - |
| Stroke2 Open | Brake pedal stroke sensor 2 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 | - |
| FR Speed Sensor Voltage Open | Front speed sensor RH voltage open detection | Error or Normal | Error: Momentary interruption Normal: Normal | - |
| FL Speed Sensor Voltage Open | Front speed sensor LH voltage open detection | Error or Normal | Error: Momentary interruption Normal: Normal | - |
| RR Speed Sensor Voltage Open | Rear speed sensor RH voltage open detection | Error or Normal | Error: Momentary interruption Normal: Normal | - |
| RL Speed Sensor Voltage Open | Rear speed sensor LH voltage open detection | Error or Normal | Error: Momentary interruption Normal: Normal | - |
| Yaw Rate Sensor Voltage Open | Yaw rate sensor voltage open detection | Error or Normal | Error: Momentary interruption Normal: Normal | - |
| Reaction Force Pressure Sensor Open | Reaction force pressure sensor open detection | Error or Normal | Error: Momentary interruption Normal: Normal | - |
| Servo Pressure Sensor Open | Servo pressure sensor open detection | Error or Normal | Error: Momentary interruption Normal: Normal | - |
| Air Bag ECU Communication Open | Airbag ECU assembly communication open detection | Error or Normal | Error: Momentary interruption Normal: Normal | - |
(f) 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.
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