Toyota Tacoma (2015-2018) Service Manual: Lost Communication with ECM / PCM "A" (U0100,U0125,U0126,U0129)
DESCRIPTION
The millimeter wave radar sensor assembly and ECM communicate with each sensor and ECU via CAN communication.
If any malfunction is detected in a CAN communication circuit, one or more CAN communication system DTCs are stored.
|
DTC No. |
Detection Item |
DTC Detection Condition |
Trouble Area |
MIL |
|---|---|---|---|---|
|
U0100 |
Lost Communication with ECM / PCM "A" |
While the vehicle speed is 36 km/h (22 mph) or more and the dynamic radar cruise control system is operating, a communication error between the ECM and the millimeter wave radar sensor assembly is detected for approximately 1 second or more. |
|
Does not come on |
|
U0125 |
Lost Communication with Yaw Rate Sensor Module |
While the vehicle speed is 36 km/h (22 mph) or more and the dynamic radar cruise control system is operating, a communication error between the yaw rate sensor and the millimeter wave radar sensor assembly is detected for approximately 1 second or more. |
|
Does not come on |
|
U0126 |
Lost Communication with Steering Angle Sensor Module |
While the vehicle speed is 36 km/h (22 mph) or more and the dynamic radar cruise control system is operating, a communication error between the steering angle sensor and the millimeter wave radar sensor assembly is detected for approximately 1 second or more. |
|
Does not come on |
|
U0129 |
Lost Communication with Brake System Control Module |
While the vehicle speed is 36 km/h (22 mph) or more and the dynamic radar cruise control system is operating, a communication error between the skid control ECU (master cylinder solenoid)*1 or skid control ECU (brake actuator assembly)*2 and the millimeter wave radar sensor assembly is detected for approximately 2.5 seconds or more. |
|
Does not come on |
- *1: for Hydraulic Brake Booster
- *2: for Vacuum Brake Booster
PROCEDURE
|
1. |
CHECK FOR DTCs (RADAR CRUISE 1 AND RADAR CRUISE 2) |
(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.
- Turn the ignition switch to ON.
- Turn the dynamic radar cruise control system on using the cruise control main switch (ON-OFF button).
- Drive the vehicle at 36 km/h (22 mph) or more for 5 seconds or more.
(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 |
Communication Error from ECM to VSC Invalid Serial Data Received (P163181)
DESCRIPTION
The ECM sends signals such as dynamic radar cruise control operation signals,
brake operation demand signals and buzzer operation demand signals to the skid control
ECU (master cylind ...
Lost Communication With ECM/PCM "A" Missing Message (U010087,U010487,U012287)
DESCRIPTION
The ECM communicates with each sensor and ECU via CAN communication.
If any malfunction is detected in a CAN communication circuit, one or more CAN
communication system DTCs are stored ...
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DESCRIPTION
This sensor detects the position of the air mix damper (for driver side) and
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(for driver side air mix).
...
Cellular Phone Inspection
PROCEDURE
1.
CHECK USAGE CONDITION
(a) Check that the vehicle and cellular phone meet the following conditions:
NOTICE:
If changing cellular phone settings, updating software, etc. is necessary, make
sure to obtain the permission of the customer before performin ...
Front Airbag Sensor RH Circuit Malfunction (B1610/13)
DESCRIPTION
The front airbag sensor RH consists of parts such as the diagnostic circuit and
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When the airbag sensor assembly receives signals from the frontal deceleration
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DTC B1610/13 is set when a ...
