Toyota Tacoma (2015-2018) Service Manual: Radar Cruise Control Presence Determination Malfunction (Engine / HV) (C1A52)

Toyota Tacoma (2015-2018) Service Manual / Cruise Control / Dynamic Radar Cruise Control System(for 2gr-fks) / Radar Cruise Control Presence Determination Malfunction (Engine / HV) (C1A52)

DESCRIPTION

DTC C1A52 is stored when the ECM cannot recognize the millimeter wave radar sensor assembly.

DTC No.	Detection Item	DTC Detection Condition	Trouble Area	MIL
C1A52	Radar Cruise Control Presence Determination Malfunction (Engine / HV)	Approximately 17 seconds after the ignition switch is turned to ON, the ECM cannot recognize the millimeter wave radar sensor assembly for approximately 1.3 seconds or more.	ECM Millimeter wave radar sensor assembly	Does not come on

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.
When the millimeter wave radar sensor assembly is replaced with a new one, adjustment of the radar sensor beam axis must be performed.
Click here
Before replacing the ECM, refer to Registration.
w/o Smart Key System: Click here

w/ Smart Key System: Click here

PROCEDURE

1.	CHECK FOR DTC (RADAR CRUISE 2)

(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.

Turn the ignition switch to ON.
Wait for 20 seconds or more.

Click here

Result	Proceed to
DTC C1A52 is not output	A
DTC C1A52 is output	B

USE SIMULATION METHOD TO CHECK

2.	REPLACE ECM

(a) Replace the ECM.

Click here

3.	CHECK FOR DTC (RADAR CRUISE 2)

(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.

Turn the ignition switch to ON.
Wait for 20 seconds or more.

Click here

Result	Proceed to
DTC C1A52 is not output	A
DTC C1A52 is output	B

END (ECM WAS DEFECTIVE)

REPLACE MILLIMETER WAVE RADAR SENSOR ASSEMBLY

Skid Control Buzzer Circuit (C1A4A)

DESCRIPTION Based on dynamic radar cruise control system operation, the forward recognition camera provides warnings to the driver by sounding the skid control buzzer. DTC C1A4A is stored when a m ...

Brake Switch "A" Circuit Open (P057113)

DESCRIPTION When the brakes are applied by the dynamic radar cruise control system, the skid control ECU (master cylinder solenoid)*1 or skid control ECU (brake actuator assembly)*2 operates the ...

Other materials:

Output Speed Sensor Circuit No Signal (P0722,P077C,P077D)
DESCRIPTION This sensor detects the rotation speed of the transmission output shaft and sends signals to the ECM. By comparing the input turbine speed signal (NT) with the output shaft speed sensor signal (SP2), the ECM detects the shift timing of the gears and appropriately controls the engi ...

Fail-safe Chart
FAIL-SAFE CHART 1. Fail-safe This function minimizes the loss of operation when any abnormality occurs in a sensor or solenoid. Fail-safe Control List Malfunction Part Function Transmission revolution sensor (NT) During a transmission revolutio ...

Theft Deterrent System Communication Line High Fixation (B279A,B279A12)
DESCRIPTION If the communication line (EFIO-IMI) to the transponder key ECU assembly is stuck high (e.g. shorted to +B), the ECM stores this DTC. DTC No. DTC Detection Condition Trouble Area DTC Output Confirmation Operation B279A*1 ...