Dtc U0129 Lost Communication With Brake System Control Module

Transmission. Toyota Rav4. Aca30, 33, 38 Gsa33 Zsa30, 35
K111F Cvt. Toyota Rav4. Aca30, 33, 38 Gsa33 Zsa30, 35

DESCRIPTION

INSPECTION PROCEDURE

CLEAR DTC AND PERFORM ROAD TEST

CHECK DTC OUTPUT (DTC U0129)

DTC U0129 Lost Communication with Brake System Control Module


DESCRIPTION

The ECM receives signals sent from the skid control ECU via the CAN communication system. When DTCs indicating a CAN communication system malfunction are output, repair the CAN communication system before repairing each corresponding ECU or sensor.

DTC Code
DTC Detection Condition
  1. Diagnosis Condition
  2. Malfunction Status
  3. Malfunction Time
  4. Other
Trouble Area
U0129
  1. The ignition switch is ON.
  2. There is no communication between the ECM and skid control ECU.
  3. 2.4 seconds
  4. 1 trip detection logic
  1. CAN communication system
  2. Brake actuator assembly (Skid control ECU)
  3. ECM

INSPECTION PROCEDURE

1.CLEAR DTC AND PERFORM ROAD TEST

  1. Clear the DTCs (RAV4_ACA30 RM000000W770CCX.html).

    HINT:
    Write down the currently output DTCs before clearing them.

  1. Start the engine and drive the vehicle at a low speed.


NEXT


2.CHECK DTC OUTPUT (DTC U0129)

  1. Connect the intelligent tester to the DLC3.

  1. Turn the ignition switch to ON.

  1. Turn the intelligent tester on.

  1. Enter the following menus: Powertrain / Engine and ECT / DTC.

  1. Read the DTCs using the tester.

    Result
    Result
    		Proceed to
    U0129 is not output
    		A
    U0129 is output
    		B



B
GO TO CAN COMMUNICATION SYSTEM (HOW TO PROCEED WITH TROUBLESHOOTING) (RAV4_ACA30 RM000001RSO01MX.html)
A

CHECK FOR INTERMITTENT PROBLEMS (RAV4_ACA30 RM00000135201PX.html)