Lexus ES: Lost Communication with ECM / PCM "A" (U0100,U0126,U0129,U0132,U023A)
DESCRIPTION
The power steering ECU (rack and pinion power steering gear assembly) receives signals from the ECM, steering sensor, skid control ECU (brake actuator assembly), AVS ECU (absorber control ECU) and forward recognition camera via CAN communication.
| DTC No. | Detection Item | DTC Detection Condition | Trouble Area | Warning Indicate | Return-to-normal Condition | Note |
|---|---|---|---|---|---|---|
| U0100 | Lost Communication with ECM / PCM "A" | Lost communication with ECM |
| EPS warning light: When an error occurs during steering assist, the warning light does not illuminate. For errors that occur before assist (at the time of the decision to start assist), the warning light illuminates. | The ECU judges the system has returned to normal | - |
| U0126 | Lost Communication With Steering Angle Sensor Module | Lost communication with steering angle sensor |
| EPS warning light: Comes on | The ECU judges the system has returned to normal | - |
| U0129 | Lost Communication with Brake System Control Module | Lost communication with skid control ECU (Brake actuator assembly) |
| EPS warning light: Comes on | The ECU judges the system has returned to normal | - |
| U0132 | Lost Communication with Ride Level Control Module | Lost communication with AVS ECU (absorber control ECU) |
| EPS warning light: Does not come on | The ECU judges the system has returned to normal | w/ Adaptive Variable Suspension System |
| U023A | Lost Communication with Front Camera Module | Lost communication with forward recognition camera |
| EPS warning light: Does not come on | The ECU judges the system has returned to normal | - |
PROCEDURE
| 1. | GO TO CAN COMMUNICATION SYSTEM |
(a) Go to CAN communication system.
Click here .gif)
| NEXT | .gif) | END |
READ NEXT:
EPS Warning Light Circuit
CAUTION / NOTICE / HINT NOTICE:
Perform this troubleshooting procedure when no DTCs are output, including DTCs related to CAN communication system malfunctions.
If the customer reports that the s
Drive Mode Select Switch Circuit
DESCRIPTION The characteristics of the electronic throttle and EPS operation change according to operation of the drive mode select switch (combination switch assembly). WIRING DIAGRAM PROCEDURE 1
Drive Mode Select Switch Circuit
DESCRIPTION The characteristics of the electronic throttle and EPS operation change according to operation of the drive mode select switch (combination switch assembly). WIRING DIAGRAM PROCEDURE 1
SEE MORE:
Diagnostic Trouble Code Chart
DIAGNOSTIC TROUBLE CODE CHART Vehicle Proximity Notification System DTC No. Detection Item Link B1350 Speaker Circuit U0129 Lost Communication with Brake System Control Module U0140 Lost Communication with Body Control Module U0293 Lost Communication wit
ECM Communication Stop Mode
DESCRIPTION Detection Item Symptom Trouble Area ECM Communication Stop Mode Any of the following conditions are met:
Communication stop for "ECM (Engine)" is indicated on the "Communication Bus Check" screen of the Techstream.
Click here
Communication stop history for "ECM (Engin
