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)

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Other materials:

Reassembly
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Speedometer Malfunction
DESCRIPTION The meter CPU receives vehicle speed signals from the skid control ECU via the CAN communication system (CAN V1 Bus). The speed sensor detects the wheel speed and sends the appropriate signals to the skid control ECU. The skid control ECU supplies power to the vehicle speed sensor ...

Operation Check
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