Lexus ES: Control Module Communication Bus "A" Off (U0073,U0126,U0129,U0140,U0155)
DESCRIPTION
These DTCs are stored when the clearance warning ECU assembly cannot receive and recognize several signals via the CAN communication line.
| DTC No. | Detection Item | DTC Detection Condition | Trouble Area |
|---|---|---|---|
| U0073 | Control Module Communication Bus "A" Off | Control module communication bus off | CAN communication system |
| U0126 | Lost Communication With Steering Angle Sensor Module | Lost communication with steering sensor | CAN communication system |
| U0129 | Lost Communication with Brake System Control Module | Lost communication with skid control ECU | CAN communication system |
| U0140 | Lost Communication with Body Control Module | Lost communication with main body ECU (multiplex network body ECU) | CAN communication system |
| U0155 | Lost Communication with Instrument Panel Cluster (IPC) Control Module | Lost communication with the combination meter assembly | CAN communication system |
HINT:
When 2 or more DTCs starting with "U" are output simultaneously, inspect the connectors and wire harnesses of each ECU.
PROCEDURE
| 1. | CHECK DTC OUTPUT |
(a) Clear the DTCs
Body Electrical > Advanced Parking Guidance/ICS/Intuitive P/A > Clear DTCs(b) Check for CAN communication system DTCs
Body Electrical > Advanced Parking Guidance/ICS/Intuitive P/A > Trouble Codes| Result | Proceed to |
|---|---|
| CAN communication system DTCs are output | A |
| No CAN communication system DTCs are output | B |
| A |  | GO TO CAN COMMUNICATION SYSTEM |
| B | | USE SIMULATION METHOD TO CHECK |
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Components
COMPONENTS ILLUSTRATION *1 REAR NO. 2 SUSPENSION ARM ASSEMBLY LH *2 REAR NO. 2 SUSPENSION ARM ASSEMBLY RH *3 REAR SUSPENSION MEMBER SUB-ASSEMBLY *4 REAR UPPER CONTROL ARM ASSEMBLY LH *5 REAR UPPER CONTROL ARM ASSEMBLY RH *6 REAR SUSPENSION MEMBER LOWER STOPPER *7
How To Proceed With Troubleshooting
CAUTION / NOTICE / HINT HINT:
Use the following procedure to troubleshoot the power trunk lid system.
*: Use the Techstream.
PROCEDURE 1. VEHICLE BROUGHT TO WORKSHOP
NEXT 2. CUSTOMER PROBLEM ANALYSIS HINT:
In troubleshooting, confirm that the problem sym
