Toyota Tundra Service Manual: 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
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

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

PROCEDURE

1.	CHECK FOR DTC (RADAR CRUISE 2)

(a) Clear the DTCs.

Click here

(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 C1A52 is not output	A
DTC C1A52 is output	B

USE SIMULATION METHOD TO CHECK

2.	REPLACE ECM

(a) Replace the ECM.

for 1UR-FE: Click here

for 3UR-FE: Click here

for 3UR-FBE: 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.

HINT:

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

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

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Toyota Tundra Owners Manual