Toyota Tacoma Quiz
Pre-collision

Lost Communication with ECM / PCM "A" (U0100,U0125,U0126,U0129)

In this manual: Pre-collision
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
~2min read
DESCRIPTION

These DTCs are stored when a communication malfunction occurs between ECUs that perform pre-collision system control.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

U0100

Lost Communication with ECM / PCM "A"

When the vehicle is being driven at a speed of 5 km/h or more, a communication error between the ECM and millimeter wave radar sensor assembly is detected for approximately 4 seconds.
  • CAN communication system
  • ECM
  • Millimeter wave radar sensor assembly

U0125

Lost Communication with Yaw Rate Sensor Module

When the vehicle is being driven at a speed of 5 km/h or more, a communication error between the yaw rate sensor (airbag sensor assembly) and millimeter wave radar sensor assembly is detected for approximately 1 second.
  • CAN communication system
  • Yaw rate sensor (Airbag sensor assembly)
  • Millimeter wave radar sensor assembly

U0126

Lost Communication with Steering Angle Sensor Module

When the ignition switch is ON, a communication error between the steering angle sensor (spiral cable with sensor sub-assembly) and millimeter wave radar sensor assembly is detected for approximately 1 second.
  • CAN communication system
  • Steering angle sensor (spiral cable with sensor sub-assembly)
  • Millimeter wave radar sensor assembly

U0129

Lost Communication with Brake System Control Module

When the ignition switch is ON, a communication error between the skid control ECU (master cylinder solenoid)*1 or skid control ECU (brake actuator assembly)*2 and millimeter wave radar sensor assembly is detected for approximately 6 seconds.
  • CAN communication system
  • Skid control ECU (master cylinder solenoid)*1 or skid control ECU (brake actuator assembly)*2
  • Millimeter wave radar sensor assembly
  • *1: for Hydraulic Brake Booster
  • *2: for Vacuum Brake Booster
PROCEDURE

  1. CHECK FOR DTCs (PRE-COLLISION SYSTEM)

(a) Clear the DTCs.

Click here (b) Make sure that the DTC detection conditions are met.

(b) Make sure that the DTC detection conditions are met.

HINT:

If the detection conditions are not met, the system cannot detect the malfunction.

(c) Check for DTCs.

Click here

Result

Proceed to

DTC U0100, U0125, U0126 and U0129 are not output

A

DTC U0100, U0125, U0126 or U0129 is output

B
A

USE SIMULATION METHOD TO CHECK
B

GO TO CAN COMMUNICATION SYSTEM

Test yourself

A quick Toyota Tacoma quiz: every answer comes with an explanation and a link to the manual page.