Toyota Tacoma 2015-2018 Service Manual: Lost Communication With Vehicle Dynamics Control Module (U0122)

Toyota Tacoma 2015-2018 Service Manual / Differential / Differential System(w/ Rear Differential Lock) / Lost Communication With Vehicle Dynamics Control Module (U0122)

DESCRIPTION

This DTC is detected if communication is lost with the skid control ECU (brake actuator assembly).

DTC No.	Detection Item	DTC Detection Condition	Trouble Area
U0122	Lost Communication with Vehicle Dynamics Control Module	Diagnosis Condition: Ignition switch turned to ON (3 seconds elapse after ignition switch is turned to ON) Malfunction Status: Communication is lost between skid control ECU and 4 wheel drive control ECU Malfunction Time: 0.72 seconds or more Other: 1 trip detection logic	CAN communication system

CAUTION / NOTICE / HINT

HINT:

for 4WD:
When the data in the skid control ECU (brake actuator assembly) is being overwritten, a message is displayed on the multi-information display and the 4LO indicator light rapidly blinks due to the 4 wheel drive control ECU detecting a communication malfunction (blinks at 0.25 second intervals (0.25 seconds on and 0.25 seconds off)), but this is not a malfunction.

for 2WD:

When the data in the skid control ECU (brake actuator assembly) is being overwritten, the rear differential lock indicator light may rapidly blink due to the 4 wheel drive control ECU detecting a communication malfunction (blinks at 0.25 second intervals (0.25 seconds on and 0.25 seconds off)), but this is not a malfunction.
Clear all DTCs, since DTCs are stored after the data in the skid control ECU (brake actuator assembly) is overwritten.

PROCEDURE

1.	PERFORM DTC

(a) Clear the DTCs (See page (b) Check if the same DTCs are output (See page ).

(b) Check if the same DTCs are output (See page Result ).

Result

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

CHECK CAN COMMUNICATION SYSTEM

USE SIMULATION METHOD TO CHECK

Lock Switch Circuit

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Differential System(w/o Differential Lock)

Precaution PRECAUTION 1. Before disassembly, clean the outside of the front and rear differential assembly and remove any sand and mud to prevent it from entering the assembly during disassembly ...

Other materials:

Adjustment
ADJUSTMENT CAUTION / NOTICE / HINT HINT: Use the same procedures for both the LH and RH sides. The procedure described below is for the LH side. Centering bolts are used to mount the door hinge to the vehicle body and door. The door cannot be adjusted with the centering bolts ...

Precaution
PRECAUTION 1. IGNITION SWITCH EXPRESSIONS (a) The type of ignition switch used on this model differs according to the specifications of the vehicle. The expressions listed in the table below are used in this section. Expression Ignition Switch (Position) Engine ...

Hydraulic Test
HYDRAULIC TEST 1. PERFORM HYDRAULIC TEST (a) Measure the line pressure. CAUTION: The line pressure test should always be performed with at least 2 people. One person should observe the condition of the wheels and wheel chocks while the other is performing the test. NOTICE: Perform ...