DESCRIPTION
The skid control ECU (brake actuator assembly) receives stop light switch signals and uses them to determine whether or not the brakes are applied. DTCs may be stored if either of the following occurs:
Stop light switch stuck on malfunction.
The accelerator and brake pedals are depressed simultaneously.*
Tech Tips
*: The skid control ECU (brake actuator assembly) may store this DTC upon judging that a stuck on malfunction has occurred when the accelerator pedal and brake pedal are depressed simultaneously. However, this does not indicate a malfunction.
| DTC No. | Detection Item | DTC Detection Condition | Trouble Area |
|---|---|---|---|
| C1249 | Open in Stop Light Switch Circuit | The vehicle speed is 10 km/h (6 mph) or more, the accelerator pedal is depressed, the master cylinder pressure is 0.5 MPa (5.09 kgf/cm2, 72 psi) or less, and the stop light switch is on for 60 seconds or more. |
|
WIRING DIAGRAM
CAUTION / NOTICE / HINT
Note
When replacing the skid control ECU (brake actuator assembly), perform system variant learning.
Inspect the fuses for circuits related to this system before performing the following procedure.
PROCEDURE
CHECK ACCELERATOR PEDAL AND BRAKE PEDAL OPERATION
Interview the customer to check if the pedals were depressed simultaneously while driving or braking.
| OK |
|---|
| The pedals were not depressed simultaneously. |
Tech Tips
The skid control ECU (brake actuator assembly) may store this DTC upon judging that a stuck on malfunction has occurred when the accelerator pedal and brake pedal are depressed simultaneously.
If the pedals were depressed simultaneously, clear the DTC because it is not a malfunction.
| Result | |||
|---|---|---|---|
|
| NG |
|
CLEAR DTC Click here |
| OK |
|
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 |
|
CHECK HARNESS AND CONNECTOR (POWER SOURCE TERMINAL) Click here |
| OK |
|
READ VALUE USING GTS (STOP LIGHT SWITCH ASSEMBLY)
Connect the GTS to the DLC3.
Turn the ignition switch to ON.
Select the Data List using the GTS.
| Tester Display | Measurement Item | Range | Normal Condition | Diagnostic Note |
|---|---|---|---|---|
| Stop Light SW | Stop light switch | ON or OFF | ON: Brake pedal depressed OFF: Brake pedal released |
- |
| Tester Display |
|---|
| Stop Light SW |
Check that the stop light switch display 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 |
|
RECONFIRM DTC
Turn the ignition switch off.
Clear the DTCs.
Turn the ignition switch off.
Start the engine.
Drive the vehicle and depress the brake pedal several times to test the stop light circuit.
Check if the same DTC is output.
| Result | ||||||
|---|---|---|---|---|---|---|
|
Tech Tips
If troubleshooting has been carried out according to Problem Symptoms Table, refer back to the table and proceed to the next step before replacing parts.
| A |
|
USE SIMULATION METHOD TO CHECK Click here |
| B |
|
REPLACE BRAKE ACTUATOR ASSEMBLY Click here |
CHECK HARNESS AND CONNECTOR (STP TERMINAL)
| *a | Front view of wire harness connector (to Skid Control ECU (Brake Actuator Assembly)) |
Turn the ignition switch off.
Make sure that there is no looseness at the locking part and the connecting part of the connector.
Disconnect the A97 skid control ECU (brake actuator assembly) connector.
Measure the voltage according to the value(s) in the table below.
| Standard Voltage | |||||||||
|---|---|---|---|---|---|---|---|---|---|
|
Tech Tips
*: The standard voltage value varies depending on the +BS terminal voltage value. The standard voltage is 85% of the +BS terminal voltage.
| Result | |||
|---|---|---|---|
|
Tech Tips
If troubleshooting has been carried out according to Problem Symptoms Table, refer back to the table and proceed to the next step before replacing parts.
| OK |
|
REPLACE BRAKE ACTUATOR ASSEMBLY Click here |
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR (STP CIRCUIT) |
CHECK HARNESS AND CONNECTOR (POWER SOURCE TERMINAL)
| *a | Front view of wire harness connector (to Stop Light Switch Assembly) |
Make sure that there is no looseness at the locking part and the connecting part of the connector.
Disconnect the A1 stop light switch assembly connector.
Measure the voltage according to the value(s) in the table below.
| Standard Voltage | ||||||
|---|---|---|---|---|---|---|
|
| Result | |||
|---|---|---|---|
|
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER SOURCE CIRCUIT) |
| OK |
|
INSPECT STOP LIGHT SWITCH ASSEMBLY
| *a | Component without harness connected (Stop Light Switch Assembly) |
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | |||||||||
|---|---|---|---|---|---|---|---|---|---|
|
| Result | |||
|---|---|---|---|
|
| NG |
|
REPLACE STOP LIGHT SWITCH ASSEMBLY Click here |
| OK |
|
CHECK HARNESS AND CONNECTOR (STP TERMINAL)
| *a | Front view of wire harness connector (to Skid Control ECU (Brake Actuator Assembly)) |
Reconnect the A1 stop light switch assembly connector.
Make sure that there is no looseness at the locking part and the connecting part of the connector.
Disconnect the A97 skid control ECU (brake actuator assembly) connector.
Measure the voltage according to the value(s) in the table below.
| Standard Voltage | |||||||||
|---|---|---|---|---|---|---|---|---|---|
|
Tech Tips
*: The standard voltage value varies depending on the +BS terminal voltage value. The standard voltage is 85% of the +BS terminal voltage.
| Result | |||
|---|---|---|---|
|
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR (STP CIRCUIT) |
| OK |
|
RECONFIRM DTC
Reconnect the A97 skid control ECU (brake actuator assembly) connector.
Clear the DTCs.
Turn the ignition switch off.
Start the engine.
Drive the vehicle and depress the brake pedal several times to test the stop light circuit.
Check if the same DTC is output.
| Result | ||||||
|---|---|---|---|---|---|---|
|
Tech Tips
If troubleshooting has been carried out according to Problem Symptoms Table, refer back to the table and proceed to the next step before replacing parts.
| A |
|
INSPECT LIGHTING SYSTEM (STOP LIGHT CIRCUIT) Click here |
| B |
|
REPLACE BRAKE ACTUATOR ASSEMBLY Click here |
CLEAR DTC
Clear the DTC.
| Result | ||
|---|---|---|
|
| NEXT |
|
END |