Brake Warning Light Remains ON [08/2013 - ]: Procedure

1. Check if ABS, VSC and/or electronically controlled brake system DTCs are output. Refer to DTC CHECK / CLEAR [08/2013 - ] .

   Result

   Result	Proceed to
   DTCs are not output.	A
   DTCs are output.	B

B → See step   16 

A: Go to next step 

1. Check if CAN communication system DTCs are output. Refer to DIAGNOSIS SYSTEM [08/2013 - ] .

   Result

   Result	Proceed to
   DTCs are not output.	A
   DTCs are output.	B

B → See step   12 

A: Go to next step 

1. Check if the skid control ECU (brake booster with master cylinder assembly) connector is securely connected.

   OK

   The connector is securely connected.

NG → CONNECT CONNECTOR TO BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY CORRECTLY 

OK: Go to next step 

1. Check the auxiliary battery voltage.

   Standard Voltage

   Tester Connection	Condition	Specified Condition
   Auxiliary battery	Power switch on (IG)	11 to 14 V
   Auxiliary battery	Power switch on (READY)	11 to 15.5 V

NG → CHARGE OR REPLACE AUXILIARY BATTERY 

OK: Go to next step 

1. Disconnect the A24 skid control ECU (brake booster with master cylinder assembly) connector.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

2. Turn the power switch on (IG).
3. Measure the voltage according to the value(s) in the table below.

   Standard Voltage

   Tester Connection	Condition	Specified Condition
   A24-16 (IG1) - Body ground	Power switch on (IG)	11 to 14 V

   TEXT IN ILLUSTRATION
   
   

   *a	Front view of wire harness connector (to Skid Control ECU (Brake Booster with Master Cylinder Assembly))

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR (IG1 CIRCUIT) 

OK: Go to next step 

1. Turn the power switch off.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   A24-28 (GND) - Body ground	Always	Below 1 Ω
   A24-27 (GND2) - Body ground	Always	Below 1 Ω
   A24-26 (GND3) - Body ground	Always	Below 1 Ω
   A24-25 (GND4) - Body ground	Always	Below 1 Ω
   A24-24 (GND5) - Body ground	Always	Below 1 Ω
   A24-23 (GND6) - Body ground	Always	Below 1 Ω

   TEXT IN ILLUSTRATION
   
   

   *a	Front view of wire harness connector (to Skid Control ECU (Brake Booster with Master Cylinder Assembly))

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR (GND CIRCUIT) 

OK: Go to next step 

1. Reconnect the A24 skid control ECU (brake booster with master cylinder assembly) connector.
2. Connect the Techstream to the DLC3.
3. Turn the power switch on (IG).
4. Select the Data List on the Techstream. Refer to DATA LIST / ACTIVE TEST [08/2013 - ] .
   ABS/VSC/TRAC
   
   

   Tester Display	Measurement Item/Range	Normal Condition	Diagnostic Note
   Parking Brake SW	Parking brake switch assembly / ON or OFF	ON: Parking brake applied OFF: Parking brake released	-

5. Using the Techstream, check if the switch condition on the Techstream changes according to parking brake operation.

   OK

   The Techstream displays ON or OFF according to parking brake operation.

NG → See step   9 

OK: Go to next step 

1. Turn the power switch off.
2. Perform the Active Test of the combination meter assembly (meter CPU) using the Techstream. Refer to DATA LIST / ACTIVE TEST [08/2013 - ] .
3. Check the combination meter assembly.

   OK

   The brake warning light / red (malfunction) turns on or off in accordance with Techstream operation.

   HINT: 

   If troubleshooting has been carried out according to Problem Symptoms Table, refer back to the table and proceed to the next step before replacing the part. Refer to PROBLEM SYMPTOMS TABLE [08/2013 - ] .

NG → See step   14 

OK → See step   11 

1. Turn the power switch off.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

2. Disconnect the A35 parking brake switch assembly connector.
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   1 (+) - Body ground	Parking brake switch assembly ON (Switch pin free)	Below 1 Ω
   1 (+) - Body ground	Parking brake switch assembly OFF (Switch pin pushed in)	10 kΩ or higher

   TEXT IN ILLUSTRATION
   
   

   *a	Component without harness connected (Parking Brake Switch Assembly)

NG → See step   13 

OK: Go to next step 

1. Disconnect the 3D main body ECU (multiplex network body ECU) connector.
2. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   3D-20 (PKB) - A35-1 (+)	Always	Below 1 Ω
   3D-20 (PKB) - Body ground	Always	10 kΩ or higher

   HINT: 

   If troubleshooting has been carried out according to Problem Symptoms Table, refer back to the table and proceed to the next step before replacing the part. Refer to PROBLEM SYMPTOMS TABLE [08/2013 - ] .

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK → See step   15