Brake Hold Standby Indicator Light Circuit [02/2019 - 12/2021]: Procedure

1. If the brake hold standby indicator light does not illuminate even though the brake hold switch (integration control and panel assembly) is pushed, check that the brake hold function operation conditions are met.
   1. The driver's door is closed.
   2. Driver's seat belt is fastened.
   3. The system is normal.

   HINT: 

   If a malfunction occurs in one of the following systems, the brake hold operated indicator light will blink. If this occurs, perform troubleshooting on the malfunctioning system.

   • Brake system
   • Electric parking brake system
   • Hybrid control system

   Result

   Proceed to
   NEXT

Result: 

NEXT 

See step  2

1. Connect the Techstream to the DLC3.
2. Turn the ignition switch to ON.
3. Select the Active Test on the Techstream.

   Refer to DATA LIST / ACTIVE TEST [02/2019 - 12/2021]

   Chassis > ABS/VSC/TRAC > Active Test 

   Tester Display	Measurement Item	Control Range	Diagnostic Note
   BH Standby Light	Brake hold standby indicator light	Indicator light ON/OFF	Observe combination meter

4. Select the Data List on the Techstream.

   Refer to DATA LIST / ACTIVE TEST [02/2019 - 12/2021]

   Chassis > ABS/VSC/TRAC > Data List 

   Tester Display	Measurement Item	Range	Normal Condition	Diagnostic Note
   BH Standby Light	Brake hold standby indicator light	ON or OFF	ON: Indicator light on OFF: Indicator light off	-

   Chassis > ABS/VSC/TRAC > Active Test 

   Active Test Display
   BH Standby Light

   Data List Display
   BH Standby Light

5. Check the operating condition of the brake hold standby indicator light when operating it using the Techstream.

   Result

   Result	Proceed to
   Brake hold standby indicator light in the Data List does not change using the Active Test.	A
   Brake hold standby indicator light in the Data List turns ON/OFF using the Active Test.	B

Result: 

A 

REPLACE BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY. Refer to  REMOVAL [02/2019 - 10/2019]  , or refer to  REMOVAL [10/2019 - 08/2020]  , or refer to  REMOVAL [08/2020 - 12/2021] 

Result: 

B 

See step  3

1. Turn the ignition switch off.
2. Perform the Active Test of the combination meter assembly (meter CPU) using the Techstream.

   Refer to DATA LIST / ACTIVE TEST [11/2018 - 08/2020] , or refer to DATA LIST / ACTIVE TEST [08/2020 - 10/2022]

   Body Electrical > Combination Meter > Active Test 

   Tester Display
   Brake Hold Indicator

3. Check the combination meter assembly.

   OK

   The brake hold standby indicator light turns on or off in accordance with the Techstream operation.

   Result

   Proceed to
   OK
   NG

Result: 

NG 

INSPECT METER / GAUGE SYSTEM. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [11/2018 - ] 

Result: 

OK 

See step  4

1. Turn the ignition switch off.
2. Remove the brake hold switch (integration control and panel assembly).

   Refer to REMOVAL [11/2018 - ]

3. Inspect the brake hold switch (integration control and panel assembly).

   Refer to INSPECTION [11/2018 - ]

   OK

   The brake hold switch (integration control and panel assembly) operates normally.

   Result

   Proceed to
   OK
   NG

Result: 

NG 

REPLACE INTEGRATION CONTROL AND PANEL ASSEMBLY. Refer to  REMOVAL [11/2018 - ] 

Result: 

OK 

See step  5

1. Disconnect the A42 skid control ECU (brake booster with master cylinder assembly) connector.
2. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   A42-10 (HZRI) - G32-24 (+B)	Always	Below 1 Ω
   A42-10 (HZRI) or G32-24 (+B) - Body ground	Always	10 kΩ or higher
   G32-15 (E) - Body ground	Always	Below 1 Ω

   Result

   Proceed to
   OK
   NG

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR 

Result: 

OK 

See step  6

1. Turn on the interior lights and check that they illuminate, and then set the switch so that the lights illuminate when the door is opened.
2. Check that the lights illuminate when the driver door is opened.

   OK

   The interior lights illuminate when the driver door is opened.

   Result

   Proceed to
   OK
   NG

Result: 

NG 

INSPECT LIGHTING SYSTEM 

w/ Headlight ECU: Refer to HOW TO PROCEED WITH TROUBLESHOOTING [11/2018 - 08/2020] , or refer to HOW TO PROCEED WITH TROUBLESHOOTING [08/2020 - 12/2021]

w/o Headlight ECU: Refer to HOW TO PROCEED WITH TROUBLESHOOTING [02/2019 - 12/2021]

w/ AFS: Refer to HOW TO PROCEED WITH TROUBLESHOOTING [02/2019 - 12/2021]

Result: 

OK 

See step  7

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

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

   Standard Voltage

   Tester Connection	Condition	Specified Condition
   A42-19 (CTY) - Body ground	Driver door open	Below 1 V
   A42-19 (CTY) - Body ground	Driver door closed	Pulse generation

   Result

   Proceed to
   OK
   NG

Result: 

OK 

REPLACE BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY. Refer to  REMOVAL [02/2019 - 10/2019]  , or refer to  REMOVAL [10/2019 - 08/2020]  , or refer to  REMOVAL [08/2020 - 12/2021] 

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR (CTY CIRCUIT)