Brake Hold Standby Indicator Light Circuit
DESCRIPTION
The brake hold
standby indicator light turns on if brake hold control is possible when
the following conditions required for operation standby are met and the
brake hold switch (electric parking brake switch assembly) is turned on
while the power switch is on (IG).
- Conditions required for operation standby:
- The driver side door is closed.
- The driver side seat belt is fastened.
- The system is normal.
WIRING DIAGRAM
CAUTION / NOTICE / HINT
NOTICE:
After
replacing the skid control ECU (brake booster with master cylinder
assembly), perform linear solenoid valve offset learning, ABS holding
solenoid valve learning, yaw rate and acceleration sensor zero point
calibration and system information memorization after performing "Reset
Memory".
Click here 
PROCEDURE
(a)
If the brake hold standby indicator light does not illuminate even
though the brake hold switch (electric parking brake switch assembly) is
pushed, check that the brake hold function operation conditions are
met.
- The driver side door is closed.
- The driver side seat belt is fastened.
- 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
|
NEXT |
 | |
| 2. |
CHECK CAN COMMUNICATION SYSTEM |
(a) Check if CAN communication system DTCs are output.
Click here
|
Result | Proceed to |
|
DTCs are not output. |
A |
| DTCs are output. |
B |
| B |
 | INSPECT CAN COMMUNICATION SYSTEM |
|
A | |
| |
| 3. |
CHECK IF BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY CONNECTOR IS SECURELY CONNECTED |
(a) 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 | |
| |
| 4. |
INSPECT COMBINATION METER ASSEMBLY |
(a) Turn the power switch off.
(b) Perform the Active Test of the combination meter assembly (meter CPU) using the Techstream.
Click here
Body Electrical > Combination Meter > Active Test
|
Tester Display |
| Brake Hold Indicator |
(c) Check the combination meter assembly.
OK:
The brake hold standby indicator light turns on or off in accordance with Techstream operation.
| NG |
| INSPECT METER / GAUGE SYSTEM |
|
OK | |
| |
| 5. |
PERFORM ACTIVE TEST USING TECHSTREAM (BRAKE HOLD STANDBY INDICATOR LIGHT) |
(a) Select the Active Test on the Techstream.
Click here
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 assembly |
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 |
(b) Check the operating condition of the brake hold standby indicator light when operating it using the Techstream.
| 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 |
| A |
| REPLACE BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY |
|
B | |
| |
| 6. |
INSPECT ELECTRIC PARKING BRAKE SWITCH ASSEMBLY |
| (a) Turn the power switch off. |
 |
|
*a | Component without harness connected
(Brake Hold Switch (Electric Parking Brake Switch Assembly)) | | |
(b) Make sure that there is no looseness at the locking part and the connecting part of the connector.
OK:
The connector is securely connected.
(c) Disconnect the G24 brake hold switch (electric parking brake switch assembly) connector.
(d) Check both the connector case and the terminals for deformation and corrosion.
OK:
No deformation or corrosion.
(e) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
|
Tester Connection | Condition |
Specified Condition |
|
8 (+B) - 16 (GND1) | Switch pushed |
Below 1 Ω |
|
8 (+B) - 16 (GND1) | Switch not pushed |
10 kΩ or higher |
| NG |
| REPLACE ELECTRIC PARKING BRAKE SWITCH ASSEMBLY |
|
OK | |
| |
| 7. |
CHECK HARNESS AND CONNECTOR (BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY - ELECTRIC PARKING BRAKE SWITCH ASSEMBLY) |
(a) Make sure that there is no looseness at the locking part and the connecting part of the connector.
OK:
The connector is securely connected.
(b) Disconnect the A35 skid control ECU (brake booster with master cylinder assembly) connector.
(c) Check both the connector case and the terminals for deformation and corrosion.
OK:
No deformation or corrosion.
(d) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
|
Tester Connection | Condition |
Specified Condition |
|
A35-20 (CSW2) - G24-8 (+B) |
Always | Below 1 Ω |
|
A35-20 (CSW2) or G24-8 (+B) - Body ground |
Always | 10 kΩ or higher |
|
G24-16 (GND1) - Body ground |
Always | Below 1 Ω |
| NG |
| REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
OK | |
| |
| 8. |
INSPECT FRONT DOOR COURTESY LIGHT SWITCH ASSEMBLY LH |
(a)
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.
(b) Check that the lights illuminate when the driver side door is opened.
OK:
The interior lights illuminate when the driver side door is opened.
| NG |
| INSPECT LIGHTING SYSTEM (COURTESY LIGHT SWITCH CIRCUIT) |
|
OK | |
| |
| 9. |
CHECK HARNESS AND CONNECTOR (CTY TERMINAL) |
| (a) Measure the voltage according to the value(s) in the table below.
Standard Voltage: |
Tester Connection | Condition |
Specified Condition | |
A35-24 (CTY) - Body ground |
Driver door open |
Below 1.5 V | |
A35-24 (CTY) - Body ground |
Driver door closed |
11 to 14 V | |
 |
|
*a | Front view of wire harness connector
(to Skid Control ECU (Brake Booster with Master Cylinder Assembly)) | | |
| OK |
| REPLACE BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY |
| NG |
| REPAIR OR REPLACE HARNESS OR CONNECTOR (CTY CIRCUIT) |
Brake Warning Light does not Come ON
DESCRIPTION
The skid
control ECU (brake booster with master cylinder assembly) is connected
to the combination meter assembly via CAN communication.
CAUTION / NOTICE / HINT
NOTICE:
After
replacing the skid control ECU (brake booster with master cylinder
assembly), perform linear solenoid valve offset learning, ABS holding
solenoid valve learning, yaw rate and acceleration sensor zero point
calibration and system information memorization after performing "Reset
Memory".
Click here 
PROCEDURE
| 1. |
CHECK CAN COMMUNICATION SYSTEM |
(a) Check if CAN communication system DTCs are output.
Click here
|
Result | Proceed to |
|
DTCs are not output. |
A |
| DTCs are output. |
B |
| B |
 | INSPECT CAN COMMUNICATION SYSTEM |
|
A |
 | |
| 2. |
PERFORM ACTIVE TEST USING TECHSTREAM (BRAKE WARNING LIGHT / RED (MALFUNCTION)) |
(a) Select the Active Test on the Techstream.
Click here
Chassis > ABS/VSC/TRAC > Active Test
|
Tester Display | Measurement Item |
Control Range | Diagnostic Note |
|
Brake Warning Light | Brake warning light / red (malfunction) |
Warning light ON/OFF | Observe combination meter assembly |
Chassis > ABS/VSC/TRAC > Data List
|
Tester Display | Measurement Item |
Range | Normal Condition |
Diagnostic Note |
|
Brake Warning Light | Brake warning light / red (malfunction) |
ON or OFF | ON: Warning light on
OFF: Warning light off |
- |
Chassis > ABS/VSC/TRAC > Active Test
|
Active Test Display |
|
Brake Warning Light |
|
Data List Display |
|
Brake Warning Light |
(b) Check the operating condition of the brake warning light / red (malfunction) when operating it using the Techstream.
| Result |
Proceed to |
| Brake warning light / red (malfunction) in the Data List does not change using the Active Test. |
A |
| Brake warning light / red (malfunction) in the Data List turns ON/OFF using the Active Test. |
B |
| A |
| REPLACE BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY |
|
B | |
| |
| 3. |
INSPECT COMBINATION METER ASSEMBLY |
(a) Perform the Active Test of the combination meter assembly (meter CPU) using the Techstream.
Click here
Body Electrical > Combination Meter > Active Test
|
Tester Display |
| Brake Warning |
(b) Check the combination meter assembly.
OK:
The brake warning light / red (malfunction) turns on or off in accordance with Techstream operation.
| OK |
| REPLACE BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY |
| NG |
| INSPECT METER / GAUGE SYSTEM |
Brake Warning Light Remains ON
DESCRIPTION
The skid
control ECU (brake booster with master cylinder assembly) is connected
to the combination meter assembly via CAN communication.
If any of the following is detected, the brake warning light / red (malfunction) remains on:
- The skid control ECU (brake booster with master cylinder assembly)
connector is disconnected from the brake booster with master cylinder
assembly.
- The brake fluid level is insufficient.
- EBD operation has been disabled.
WIRING DIAGRAM
CAUTION / NOTICE / HINT
NOTICE:
- After replacing the skid control ECU (brake booster with master cylinder
assembly), perform linear solenoid valve offset learning, ABS holding
solenoid valve learning, yaw rate and acceleration sensor zero point
calibration and system information memorization after performing "Reset
Memory".
Click here 
- Inspect the fuses for circuits related to this system before performing the following procedure.
- Before performing this procedure, depress the brake pedal and confirm that the stop lights illuminate.
PROCEDURE
(a) Check that all of the following conditions required for the brake warning light / red (malfunction) to turn off are met:
|
NEXT |
 | |
(a) Check if ABS, VSC and/or electronically controlled brake system DTCs are output.
Click here
Chassis > ABS/VSC/TRAC > Trouble Codes
|
Result | Proceed to |
|
DTCs are not output. |
A |
| DTCs are output. |
B |
| B |
 | REPAIR CIRCUITS INDICATED BY OUTPUT DTCS |
|
A | |
| |
| 3. |
CHECK CAN COMMUNICATION SYSTEM |
(a) Check if CAN communication system DTCs are output.
Click here
|
Result | Proceed to |
|
DTCs are not output. |
A |
| DTCs are output. |
B |
| B |
| INSPECT CAN COMMUNICATION SYSTEM |
|
A | |
| |
| 4. |
CHECK IF BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY CONNECTOR IS SECURELY CONNECTED |
(a) 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 | |
| |
| 5. |
CHECK AUXILIARY BATTERY |
(a) 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 | |
| |
| 6. |
CHECK HARNESS AND CONNECTOR (IG1 TERMINAL) |
| (a) Turn the power switch off. |
 |
|
*a | Front view of wire harness connector
(to Skid Control ECU (Brake Booster with Master Cylinder Assembly)) | | |
(b) Make sure that there is no looseness at the locking part and the connecting part of the connector.
OK:
The connector is securely connected.
(c) Disconnect the A35 skid control ECU (brake booster with master cylinder assembly) connector.
(d) Check both the connector case and the terminals for deformation and corrosion.
OK:
No deformation or corrosion.
(e) Turn the power switch on (IG).
(f) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
|
Tester Connection | Condition |
Specified Condition |
|
A35-23 (IG1) - Body ground |
Power switch on (IG) |
11 to 14 V |
| NG |
| REPAIR OR REPLACE HARNESS OR CONNECTOR (IG1 CIRCUIT) |
|
OK | |
| |
| 7. |
CHECK HARNESS AND CONNECTOR (GND TERMINAL) |
| (a) Turn the power switch off. |
 |
|
*a | Front view of wire harness connector
(to Skid Control ECU (Brake Booster with Master Cylinder Assembly)) | | |
(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
|
Tester Connection | Condition |
Specified Condition |
|
A35-26 (GND1) - Body ground |
Always | Below 1 Ω |
|
A35-39 (GND2) - Body ground |
Always | Below 1 Ω |
| NG |
| REPAIR OR REPLACE HARNESS OR CONNECTOR (GND CIRCUIT) |
|
OK | |
| |
| 8. |
READ VALUE USING TECHSTREAM (BRAKE WARNING LIGHT / RED (MALFUNCTION)) |
(a) Reconnect the A35 skid control ECU (brake booster with master cylinder assembly) connector.
(b) Select the Data List on the Techstream.
Click here
Chassis > ABS/VSC/TRAC > Data List
|
Tester Display | Measurement Item |
Range | Normal Condition |
Diagnostic Note |
|
Brake Warning Light | Brake warning light / red (malfunction) |
ON or OFF | ON: Warning light on
OFF: Warning light off |
- |
Chassis > ABS/VSC/TRAC > Data List
|
Tester Display |
| Brake Warning Light |
(c) Check the Techstream display condition of the brake warning light / red (malfunction).
| Result |
Proceed to |
| ON is displayed. |
A |
| OFF is displayed. |
B |
| A |
| REPLACE BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY |
| B |
| INSPECT METER / GAUGE SYSTEM |
