DESCRIPTION
Upon receiving the hill-start assist control, dynamic radar cruise control, brake hold control or trailer sway control operating signal from the skid control ECU (brake booster with master cylinder assembly), the relay contact turns on and the stop lights come on.
Upon receiving the emergency brake signal operating signal from the skid control ECU (brake booster with master cylinder assembly), the relay contact turns on and the stop light blinks.
| DTC No. | Detection Item | INF Code | DTC Detection Condition | Trouble Area | Note |
|---|---|---|---|---|---|
| C1380/64 | Stop Light Control Relay Malfunction | 761 762 |
|
|
VSC DTC |
WIRING DIAGRAM
CAUTION / NOTICE / HINT
Note
When replacing the skid control ECU (brake booster with master cylinder assembly), perform initialization and calibration of the linear solenoid valve.
Inspect the fuses for circuits related to this system before performing the following procedure.
Tech Tips
When C1249/49 is output together with C1380/64, inspect and repair the trouble areas indicated by C1249/49 first.
PROCEDURE
CHECK STOP LIGHT OPERATION
Check that the stop lights come on when the brake pedal is depressed and go off when the brake pedal is released.
| OK | ||||||
|---|---|---|---|---|---|---|
|
| Result | |||
|---|---|---|---|
|
| NG |
|
INSPECT LIGHTING SYSTEM (STOP LIGHT CIRCUIT) Click here |
| OK |
|
READ VALUE USING GTS (STOP LIGHT SWITCH ASSEMBLY)
Connect the GTS to the DLC3.
Turn the power switch on (IG).
Select the Data List on the GTS.
| Tester Display | Measurement Item | Range | Normal Condition | Diagnostic Note |
|---|---|---|---|---|
| Stop Light SW | Stop light switch assembly | ON or OFF | ON: Brake pedal depressed OFF: Brake pedal released |
- |
| Tester Display |
|---|
| Stop Light SW |
Check that the stop light switch assembly condition observed on the GTS changes according to brake pedal operation.
| OK |
|---|
| The GTS displays ON or OFF according to brake pedal operation. |
| Result | |||
|---|---|---|---|
|
| NG |
|
CHECK HARNESS AND CONNECTOR (STP TERMINAL) Click here |
| OK |
|
PERFORM ACTIVE TEST USING GTS (STOP LIGHT CONTROL ECU ASSEMBLY)
Select the Active Test on the GTS.
| Tester Display | Measurement Item | Control Range | Diagnostic Note |
|---|---|---|---|
| Stop Light Relay | Stop light control ECU assembly (stop light control relay) | ECU (Relay) ON/OFF | Stop lights come on |
| EBS Relay | Stop light control ECU assembly output (Emergency brake signal operation) | Stop light control ECU assembly (Emergency brake signal operation) ON/OFF |
|
| Tester Display |
|---|
| Stop Light Relay |
| Tester Display |
|---|
| EBS Relay |
Perform the Active Test of the stop light control ECU assembly using the GTS.
Select the Data List on the GTS.
| Tester Display | Measurement Item | Range | Normal Condition | Diagnostic Note |
|---|---|---|---|---|
| Stop Light Relay Output | Stop light control ECU assembly (stop light control relay) output | ON or OFF | ON: ECU (Relay) output on OFF: ECU (Relay) output off |
- |
| EBS Relay | Stop light control ECU assembly (Emergency brake signal operation status) | ON or OFF | ON: During emergency brake signal control OFF: Not during emergency brake signal control |
Hazard warning switch off (when performing Active Test, stop light blinks due to depressing brake pedal when Data List ON) |
| Tester Display |
|---|
| Stop Light Relay Output |
| EBS Relay |
Check for stop light control ECU assembly operation using the Data List and stop light operation by performing the Active Test.
| Result | ||||||
|---|---|---|---|---|---|---|
|
| B |
|
INSPECT STOP LIGHT CONTROL ECU ASSEMBLY Click here |
| A |
|
CHECK HARNESS AND CONNECTOR (STP2 TERMINAL)
| *a | Front view of wire harness connector (to Skid Control ECU (Brake Booster with Master Cylinder Assembly)) |
Turn the power switch off.
Make sure that there is no looseness at the locking part and the connecting part of the connector.
Disconnect the A57 skid control ECU (brake booster with master cylinder assembly) connector.
Measure the voltage according to the value(s) in the table below.
| Standard Voltage | |||||||||
|---|---|---|---|---|---|---|---|---|---|
|
| Result | |||
|---|---|---|---|
|
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR (STP CIRCUIT) |
| OK |
|
RECONFIRM DTC
Reconnect the A57 skid control ECU (brake booster with master cylinder assembly) connector.
Clear the DTCs.
Turn the power switch on (READY).
Perform a road test.
Check if the same DTC is output.
| Result | ||||||
|---|---|---|---|---|---|---|
|
| A |
|
USE SIMULATION METHOD TO CHECK Click here |
| B |
|
REPLACE BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY for LHD: Click here |
INSPECT STOP LIGHT CONTROL ECU ASSEMBLY
Turn the power switch off.
Check the stop light control ECU assembly.
for LHD: Click here
for RHD: Click here
| OK |
|---|
| The stop light control ECU assembly is normal. |
| Result | |||
|---|---|---|---|
|
| NG |
|
REPLACE STOP LIGHT CONTROL ECU ASSEMBLY for LHD: Click here |
| OK |
|
CHECK HARNESS AND CONNECTOR (BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY - STOP LIGHT CONTROL ECU ASSEMBLY)
Make sure that there is no looseness at the locking part and the connecting part of the connectors.
Disconnect the A57 skid control ECU (brake booster with master cylinder assembly) connector.
Disconnect the A3 stop light control ECU assembly connector.
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | |||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
| Result | |||
|---|---|---|---|
|
| OK |
|
REPLACE BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY for LHD: Click here |
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR (STP0 CIRCUIT) |
CHECK HARNESS AND CONNECTOR (STP TERMINAL)
| *a | Front view of wire harness connector (to Skid Control ECU (Brake Booster with Master Cylinder Assembly)) |
Turn the power switch off.
Make sure that there is no looseness at the locking part and the connecting part of the connector.
Disconnect the A57 skid control ECU (brake booster with master cylinder assembly) connector.
Measure the voltage according to the value(s) in the table below.
| Standard Voltage | |||||||||
|---|---|---|---|---|---|---|---|---|---|
|
| Result | |||
|---|---|---|---|
|
| OK |
|
REPLACE BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY for LHD: Click here |
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR (STP CIRCUIT) |