Toyota Tacoma 2015-2018 Service Manual: Skid Control Buzzer Circuit (C1AA7)

Toyota Tacoma 2015-2018 Service Manual / Cruise Control / Forward Recognition Camera System / Skid Control Buzzer Circuit (C1AA7)

DESCRIPTION

The forward recognition camera operates the pre-collision warning by sending a buzzer request signal to the skid control buzzer.

If the forward recognition camera detects a malfunction in the skid control buzzer circuit, it will output DTC C1AA7.

DTC No.	Detection Item	DTC Detection Condition	Trouble Area
C1AA7	Skid Control Buzzer Circuit	When the ignition switch is turned to ON and the pre-collision warning is operating, and one of the following conditions is met (1 trip detection logic*): A buzzer request signal is sent to the skid control buzzer but the buzzer does not sound for 1 second or more. A buzzer request signal is not sent to the skid control buzzer but the buzzer sounds for 1 second or more. There is no buzzer sounding request and an open circuit is detected in the skid control buzzer.	Skid control buzzer Forward recognition camera Harness or connector

*: Only output while a malfunction is present.

DTC Detection Conditions

		Vehicle Condition
		Pattern 1	Pattern 2	Pattern 3
Diagnosis Condition	When the ignition switch is turned to ON and the pre-collision warning is operating	○	○	○
Malfunction Status	A buzzer request signal is sent to the skid control buzzer but the buzzer does not sound	○	-	-
	A buzzer request signal is not sent to the skid control buzzer but the buzzer sounds	-	○	-
	There is no buzzer sounding request and an open circuit is detected in the skid control buzzer	-	-	○
Detection Time		1 second or more	1 second or more	1 second or more
Number of Trips		1 trip	1 trip	1 trip

HINT:

DTC will be output when conditions for either of the patterns in the table above are met.

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

Inspect the fuses for circuits related to this system before performing the following procedure.
When replacing the forward recognition camera, always replace it with a new one. If a forward recognition camera which was installed to another vehicle is used, the information stored in the forward recognition camera will not match the information from the vehicle. As a result, a DTC may be stored.
If the forward recognition camera has been replaced with a new one, be sure to perform Forward Recognition Camera Axis Adjustment.
Click here

PROCEDURE

1.	CHECK FOR DTCs (FORWARD RECOGNITION CAMERA SYSTEM)

(a) Clear the DTCs.

Click here (b) Perform the Active Test according to the display on the Techstream.

(b) Perform the Active Test according to the display on the Techstream.

Click here NOTICE:

NOTICE:

Perform the Active Test for 1 second or more.

HINT:

Performing the Active Test for 1 second or more causes DTC C1AA7 to be stored if the DTC detection conditions are met.

Tester Display	Measurement Item	Control Range	Diagnostic Note
PCS Buzzer	Skid control buzzer	ON / OFF	Test possible with ignition switch ON, vehicle stopped

Click here

Result	Proceed to
DTC C1AA7 is not output	A
DTC C1AA7 is output	B

USE SIMULATION METHOD TO CHECK

2.	CHECK TERMINAL VOLTAGE

(a) Disconnect the skid control buzzer connector.

*a	Front view of wire harness connector (to Skid Control Buzzer)

(b) Measure the voltage according to the value(s) in the table below.

Standard Voltage:

Tester Connection	Switch Condition	Specified Condition
N38-2 (IG1) - Body ground	Ignition switch ON	11 to 14 V
N38-2 (IG1) - Body ground	Ignition switch off	Below 1 V

REPAIR OR REPLACE HARNESS OR CONNECTOR (SKID CONTROL BUZZER - BATTERY)

3.	CHECK HARNESS AND CONNECTOR (SKID CONTROL BUZZER - FORWARD RECOGNITION CAMERA)

(a) Disconnect the N38 skid control buzzer connector.

(b) Disconnect the F46 forward recognition camera connector.

Standard Resistance:

Tester Connection	Condition	Specified Condition
N38-1 (BZ) - F46-8 (BZ)	Always	Below 1 Ω
N38-1 (BZ) or F46-8 (BZ) - Body ground	Always	10 kΩ or higher

(d) Connect the F46 forward recognition camera connector.

(e) Connect the N38 skid control buzzer connector.

GO TO STEP 6

4.	REPAIR OR REPLACE HARNESS OR CONNECTOR (SKID CONTROL BUZZER - FORWARD RECOGNITION CAMERA)

(a) Repair or replace the harness or connector.

5.	CHECK FOR DTCs (FORWARD RECOGNITION CAMERA SYSTEM)

(a) Clear the DTCs.

Click here (b) Perform the Active Test according to the display on the Techstream.

(b) Perform the Active Test according to the display on the Techstream.

Click here NOTICE:

NOTICE:

Perform the Active Test for 1 second or more.

HINT:

Performing the Active Test for 1 second or more causes DTC C1AA7 to be stored if the DTC detection conditions are met.

Tester Display	Measurement Item	Control Range	Diagnostic Note
PCS Buzzer	Skid control buzzer	ON / OFF	Test possible with ignition switch ON, vehicle stopped

Click here

Result	Proceed to
DTC C1AA7 is not output	A
DTC C1AA7 is output	B

END

6.	INSPECT SKID CONTROL BUZZER (CONFIRM BUZZER OPERATION)

(a) Turn the ignition switch to ON.

(b) Check if the skid control buzzer is sounding.

Result	Proceed to
The skid control buzzer does not sound when the ignition switch is turned to ON	A
The skid control buzzer sounds continuously when the ignition switch is turned to ON	B

GO TO STEP 8

7.	INSPECT SKID CONTROL BUZZER (UNIT INSPECTION)

(a) Remove the skid control buzzer.

Click here (b) Inspect the skid control buzzer.

(b) Inspect the skid control buzzer.

Click here

Result	Proceed to
Skid control buzzer is abnormal	A
Skid control buzzer is normal	B

GO TO STEP 9

8.	REPLACE SKID CONTROL BUZZER

(a) Replace the skid control buzzer.

Click here

9.	CHECK FOR DTCs (FORWARD RECOGNITION CAMERA SYSTEM)

(a) Clear the DTCs.

Click here (b) Perform the Active Test according to the display on the Techstream.

(b) Perform the Active Test according to the display on the Techstream.

Click here NOTICE:

NOTICE:

Perform the Active Test for 1 second or more.

HINT:

Performing the Active Test for 1 second or more causes DTC C1AA7 to be stored if the DTC detection conditions are met.

Tester Display	Measurement Item	Control Range	Diagnostic Note
PCS Buzzer	Skid control buzzer	ON / OFF	Test possible with ignition switch ON, vehicle stopped

Click here

Result	Proceed to
DTC C1AA7 is not output	A
DTC C1AA7 is output	B

END

REPLACE FORWARD RECOGNITION CAMERA

Vehicle Speed Sensor Circuit (C1AA3)

DESCRIPTION The forward recognition camera receives vehicle speed signals from the skid control ECU. If the skid control ECU receives a vehicle speed sensor malfunction signal, it informs the for ...

FCM Destination Information Unmatched (C1AA1)

DESCRIPTION When the forward recognition camera is replaced with a new one, the new forward recognition camera attempts to store country specification information received from the main body ECU ...

Other materials:

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 ...

Acceleration Sensor Stuck Malfunction (C1232,C1243,C1245)
DESCRIPTION The skid control ECU (brake actuator assembly) receives signals from the yaw rate and acceleration sensor (airbag sensor assembly) via the CAN communication system. The airbag sensor assembly has a built-in acceleration sensor and detects the vehicle condition. If there is troub ...

Inspection
INSPECTION PROCEDURE 1. INSPECT HAZARD WARNING SIGNAL SWITCH ASSEMBLY (AIR CONDITIONING CONTROL ASSEMBLY) (a) Check the resistance. (1) Measure the resistance according to the value(s) in the table below. Text in Illustration *a Component withou ...