DTC C1A05: Stop Light Switch Circuit [10/2015 - ]: Procedure

1. Disconnect the stop light switch assembly connector.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   *a	Front view of wire harness connector (to Stop Light Switch Assembly)

2. Measure the voltage and resistance according to the value(s) in the table below.

   Standard Voltage

   Tester Connection	Condition	Specified Condition
   A5-1 (B) - A52-3 (GND)	Always	11 to 14 V

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   A5-3 (GND) - Body ground	Always	Below 1 Ω

   Result

   Proceed to
   OK
   NG

Result:  2

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR (STOP LIGHT SWITCH ASSEMBLY - BATTERY AND BODY GROUND) 

Result:  1

OK 

See step  2

1. Disconnect the driving support ECU assembly connector.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   *a	Front view of wire harness connector (to Driving Support ECU Assembly)

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

   Standard Voltage

   Tester Connection	Condition	Specified Condition
   N160-1 (ST1-) - Body ground	Power switch on (IG), brake pedal released	7.5 to 14 V
   	Power switch on (IG), brake pedal depressed	0 to 1.5 V
   N160-15 (STP-) - Body ground	Brake pedal released	0 to 1.5 V
   	Brake pedal depressed	7.5 to 14 V

   Result

   Proceed to
   OK
   NG

Result:  2

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR 

Result:  1

OK 

See step  3

1. Temporarily replace the stop light switch assembly with a new or normally functioning one.

   Refer to REMOVAL [09/2014 - ]

2. Clear the DTCs.

   Refer to DTC CHECK / CLEAR [10/2015 - ]

3. Make sure that the DTC detection conditions are met.

   HINT: 

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

   1. Turn the power switch on (IG).
   2. Turn the the dynamic radar cruise control system on using the cruise control main switch (ON/OFF).
   3. Depress the brake pedal.
4. Check for DTCs.

   Refer to DTC CHECK / CLEAR [10/2015 - ]

   Result

   Result	Proceed to
   DTC C1A05 is not output	A
   DTC C1A05 is output	B

Result:  1

A 

END (STOP LIGHT SWITCH ASSEMBLY WAS DEFECTIVE) 

Result:  2

B 

REPLACE DRIVING SUPPORT ECU ASSEMBLY. Refer to  REMOVAL [10/2015 - ]