Toyota Tacoma (2015-2018) Service Manual: Lost Communication with ECM / PCM "A" (U0100,U0125,U0126,U0129)
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 (4 mph) or more, a communication error between the ECM and millimeter wave radar sensor assembly is detected for approximately 4 seconds. |
|
|
U0125 |
Lost Communication with Yaw Rate Sensor Module |
When the vehicle is being driven at a speed of 5 km/h (4 mph) 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. |
|
|
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. |
|
|
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. |
|
- *1: for Hydraulic Brake Booster
- *2: for Vacuum Brake Booster
PROCEDURE
|
1. |
CHECK FOR DTCs (PRE-COLLISION SYSTEM) |
(a) Clear the DTCs.
Click here .gif)
(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 | .gif) |
USE SIMULATION METHOD TO CHECK |
| B | |
GO TO CAN COMMUNICATION SYSTEM |
Heater Circuit (C1AAE)
DESCRIPTION
If the forward recognition camera detects a malfunction in the camera heater
(forward recognition hood) circuit, it will output a malfunction signal to the millimeter
wave radar senso ...
Lost Communication with Cruise Control Front Distance Range Sensor (U0235)
DESCRIPTION
The millimeter wave radar sensor assembly is connected to the skid control ECU
(master cylinder solenoid)*1 or skid control ECU (brake actuator assembly)*2 via
CAN communication. If c ...
Other materials:
Lost Communication with ECM / PCM (U0100,U0140,U0142,U0155,U1117)
DESCRIPTION
These DTCs are stored when there is a CAN communication malfunction between the
certification ECU (smart key ECU assembly), ECM, main body ECU (multiplex network
body ECU) or combination meter assembly, and data from the option connector (bus
buffer ECU) cannot be received.
HINT: ...
Speaker Circuit
DESCRIPTION
If there is a short in a speaker circuit, the stereo component amplifier assembly*1
or navigation receiver assembly*2 detects it and stops output to the speakers.
Thus sound cannot be heard from the speakers even if there is no malfunction
in the stereo component amplifier assembly ...
Problem Symptoms Table
PROBLEM SYMPTOMS TABLE
HINT:
Use the table below to help determine the cause of problem symptoms.
If multiple suspected areas are listed, the potential causes of the symptoms
are listed in order of probability in the "Suspected Area" column of the
table. Check each sy ...
