Toyota Tacoma Quiz
Vf2cm Transfer

Lost Communication with ECM / PCM "A" (U0100,U0122)

In this manual: Vf2cm Transfer
Introduction — 15Maintenance — 8Audio / Video — 94Garage Door Opener — 7Navigation / Multi Info Display — 84Park Assist / Monitoring — 86Brake — 50Brake Control / Dynamic Control Systems — 165Parking Brake — 52gr-fks Charging — 252gr-fks Cooling — 212gr-fks Emission Control — 132gr-fks Engine Control — 322gr-fks Engine Mechanical — 332gr-fks Exhaust — 92gr-fks Fuel — 422gr-fks Ignition — 62gr-fks Intake — 72gr-fks Lubrication — 152gr-fks Starting — 38Ac60e Automatic Transmission / Transaxle — 146Axle — 19Clutch — 20Cruise Control — 168Differential — 50Drive Shaft — 6Propeller Shaft — 23Rc62f Manual Transmission / Transaxle — 34Suspension — 22Tire And Wheel — 39Vf2cm Transfer — 44Can Communication — 45Multiplex Communication — 20Power Distribution — 5Power Steering — 29Steering Column — 29Air Conditioning — 108Door Lock — 88Engine Hood / Door — 16Engine Immobiliser — 47Exterior — 55Horn — 5Interior — 18Interior Panel — 8Lighting — 93Meter / Gauge / Display — 31Mirror — 22Other System — 24Pre-collision — 40Seat — 52Seat Belt — 40Sliding Roof — 26Supplemental Restraint Systems — 139Theft Deterrent — 20Window / Glass — 53Wiper / Washer — 24
~1min read
DESCRIPTION

This DTC is output when communication is lost with the skid control ECU (brake actuator assembly) or ECM.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

U0100

Lost Communication with ECM / PCM "A"
  • Diagnosis Condition: Ignition switch turned to ON (3 seconds elapse after ignition switch is turned to ON)
  • Malfunction Status: Communication is lost between ECM and 4 wheel drive control ECU
  • Malfunction Time: 1.85 seconds or more
  • Other: 1 trip detection logic

CAN communication system

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

NOTICE:

  • When the data in the ECM and skid control ECU (brake actuator assembly) is being overwritten, a message is displayed on the multi-information display and the 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.
  • Clear all DTCs, since DTCs are stored after the data in the ECM or 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
A

CHECK CAN COMMUNICATION SYSTEM
B

USE SIMULATION METHOD TO CHECK

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