Lexus RX (RX 350L, RX450h) 2016-2026 Repair Manual: Lost Communication with ECM / PCM "A" (U0100,U0125,U0126,U0129,U0142)

DESCRIPTION

These DTCs are stored if there is a malfunction in the CAN communication system connected to the blind spot monitor sensor.

HINT:

If CAN communication system DTCs are stored, they may also be stored for other systems.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

U0100

Lost Communication with ECM / PCM "A"

Lost communication with ECM

CAN communication system

U0125

Lost Communication with Yaw Rate Sensor Module

Lost communication with airbag sensor assembly*1 or yaw rate and acceleration sensor*2

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 brake system

CAN communication system

U0142

Lost Communication with Body Control Module "B"

Lost communication with main body ECU

CAN communication system

  • *1: for Optitron Meter Type
  • *2: for TFT Meter Type

CAUTION / NOTICE / HINT

NOTICE:

When checking for DTCs, make sure that the blind spot monitor system is turned on.

PROCEDURE

1.

CHECK DTC

(a) Turn the engine switch off.

(b) Turn the engine switch on (IG).

(c) Recheck for DTCs and check if the same DTC is output again.

Body Electrical > Blind Spot Monitor Master > Trouble Codes Body Electrical > Blind Spot Monitor Slave > Trouble Codes

Result

Proceed to

DTCs are output.

A

No DTCs are output.

B

HINT:

  • If CAN communication system DTCs are stored, they may also be stored for other systems.
  • If the CAN communication system has been inspected and repaired, the DTCs will not be output when rechecking for DTCs.
  • If these DTCs are output frequently, duplicate the conditions that cause the problem symptoms and perform the inspection again, even if the DTCs were not output when rechecking for DTCs.

    Click here

A

GO TO CAN COMMUNICATION SYSTEM

B

USE SIMULATION METHOD TO CHECK

    Slave Module Horizontal Axis Misalignment (C1AC2)
    DESCRIPTION This DTC is stored when the angle of the blind spot monitor sensor RH deviates more than the allowable range from the horizontal axis. HINT: If a drum tester such as a speedometer teste ...

    Lost Communication with Blind Spot Monitor Slave Module (U0232)
    DESCRIPTION This DTC is stored when the blind spot monitor sensor LH judges that there is a communication problem with the blind spot monitor sensor RH. DTC No. Detection Item DTC Detection Con ...

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