Toyota Tacoma (2015-2018) Service Manual: Lost Communication with Cruise Control Front Distance Range Sensor (U0235)

Toyota Tacoma (2015-2018) Service Manual / Pre-collision / Pre-collision System / 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 communication with the skid control ECU (master cylinder solenoid)*1 or skid control ECU (brake actuator assembly)*2 stops, the millimeter wave radar sensor assembly stores DTC U0235.

*1: for Hydraulic Brake Booster
*2: for Vacuum Brake Booster

DTC No.	Detection Item	DTC Detection Condition	Trouble Area
U0235	Lost Communication with Cruise Control Front Distance Range Sensor	When the ignition switch is ON, a communication error between the millimeter wave radar sensor assembly and skid control ECU (master cylinder solenoid)1 or skid control ECU (brake actuator assembly)2 is detected for approximately 2 seconds.	CAN communication system Vehicle stability control system Millimeter wave radar sensor assembly

*1: for Hydraulic Brake Booster
*2: for Vacuum Brake Booster

CAUTION / NOTICE / HINT

NOTICE:

When replacing the millimeter wave radar sensor assembly, always replace it with a new one. If a millimeter wave radar sensor assembly which was installed to another vehicle is used, the information stored in the millimeter wave radar sensor assembly will not match the information from the vehicle. As a result, a DTC may be stored.
If the millimeter wave radar sensor assembly has been replaced, be sure to perform millimeter wave radar sensor assembly adjustment.
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The pre-collision system uses the CAN communication system. First, confirm that there are no malfunctions in the CAN communication system. Refer to How to Proceed with Troubleshooting.
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PROCEDURE

1.	CHECK FOR DTCs (VEHICLE STABILITY CONTROL SYSTEM)

(a) Check for DTCs.

Click here

Result	Proceed to
Vehicle stability control system DTCs are not output	A
Vehicle stability control system DTCs are output	B

GO TO VEHICLE STABILITY CONTROL SYSTEM

2.	TEST MODE INSPECTION (VEHICLE STABILITY CONTROL SYSTEM)

HINT:

When entering Test Mode (Signal Check), the skid control ECU (master cylinder solenoid)*1 or skid control ECU (brake actuator assembly)*2 communicates with the millimeter wave radar sensor assembly to judge whether the vehicle is equipped with the pre-collision system. Therefore, do not exit Test Mode (Signal Check) within 5 seconds of entering Test Mode (Signal Check).

*1: for Hydraulic Brake Booster
*2: for Vacuum Brake Booster

(a) Procedure to enter Test Mode

(1) Turn the ignition switch off.

(2) Check that the steering wheel is centered.

(3) Check that the shift lever is in P.

(4) Connect the Techstream to the DLC3.

(5) Turn the ignition switch to ON.

(6) Turn the Techstream on.

(7) Switch the skid control ECU (master cylinder solenoid)*1 or skid control ECU (brake actuator assembly)*2 to Test Mode (Signal Check) using the Techstream. Enter the following menus: Chassis / ABS/VSC/TRAC / Utility / Signal Check.

*1: for Hydraulic Brake Booster
*2: for Vacuum Brake Booster

HINT:

Do not exit Test Mode (Signal Check) within 5 seconds of entering Test Mode (Signal Check). If Test Mode (Signal Check) is exited within 5 seconds of entering Test Mode (Signal Check), DTC U0235 may be stored. If DTC U0235 is output after exiting Test Mode (Signal Check), enter Test Mode (Signal Check) again, wait at least 5 seconds, then recheck for DTCs.

(8) Check that the ABS warning and slip indicator lights come on for several seconds and then blink in the Test Mode (Signal Check) pattern.

HINT:

If the ABS warning and slip indicator lights do not blink, inspect the ABS warning and slip indicator light circuits.

(b) End Test Mode (Signal Check)

(1) Turn the ignition switch off to exit mode.

(2) Disconnect the Techstream.

3.	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.

Click here

Result	Proceed to
DTC U0235 is not output	A
DTC U0235 is output	B

END

REPLACE MILLIMETER WAVE RADAR SENSOR ASSEMBLY

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