VSA DTC Troubleshooting: 68-12
DTC 68-12: Brake Pedal Position Switch Stuck ON
NOTE: Before you troubleshoot, record all freeze data and any on-board snapshot, and review the general troubleshooting information.

DTC Description
DTC
Freeze Frame
68-12 Brake Pedal Position Switch Stuck ON
    

1.
VSA modulator-control unit performance check:

VSA modulator-control unit performance check
?1.
Start the engine.

?2.
Check the parameter(s) below with the HDS. Do not press the brake pedal.
Signal
Current conditions
Values
Unit
BRAKE PRESSURE
    

Is there 10 MPa or more?

     
YES
     
     
     
Go to step 2.
     
NO
     
     
     
Go to step 3.
2.
Brake pedal height check:

Brake pedal height check
?1.
Check the brake pedal height.

Is the brake pedal height OK?

     
YES
     
     
     
Go to step 7.
     
NO
     
     
     
3.
Brake pedal position switch performance check 1:

Brake pedal position switch performance check 1
?1.
Check the parameter(s) below with the HDS while pressing the brake pedal.
Signal
Current conditions
Values
Unit
BRAKE SWITCH
    

Does it indicate ON when the pedal is pressed, and OFF when the pedal is released?

     
YES
     
     
     
Intermittent failure, the system is OK at this time. Refer to intermittent failures troubleshooting.?
     
NO
     
     
     
Go to step 4.
4.
Brake pedal position switch performance check 2:

Brake pedal position switch performance check 2
?1.
Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.

?2.
Disconnect the following connector.

?3.
Check the parameter(s) below with the HDS.
Signal
Current conditions
Values
Unit
BRAKE SWITCH
    

Does the indicator change from ON to OFF?

     
YES
     
     
     
     
NO
     
     
     
Go to step 5.
5.
Shorted wire check (STOP SW line to power):

Shorted wire check (STOP SW line to power)
?1.
Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.

?2.
Short the SCS line with the HDS.


?3.
Disconnect the following connector.

?4.
Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode.

?5.
Measure the voltage between test points 1 and 2.
Test condition
IG ON (II) or ON mode
 
Brake pedal position switch 4P connector: disconnected
 
PCM connector A (51P): disconnected
Test circuit
STOP SW
Test point 1
Brake pedal position switch 4P connector No. 1 (LT GRN)
Test point 2
Body ground


Is there 0.1 V or more?

     
YES
     
     
     
Repair a short to power in the wire between the PCM and the brake pedal position switch.?
     
NO
     
     
     
The STOP SW wire is OK. Go to step 6.
6.
PCM check (update or substitution):

PCM check (update or substitution)
?1.
Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.

?2.
Reconnect the following connectors.

?3.
Update the PCM if it does not have the latest software, or substitute a known-good PCM.

?4.
Clear the DTC with the HDS.


?5.
Turn the ignition switch to LOCK (0), then turn it to ON (II) again, or select the OFF mode, then the ON mode.

?6.
Check for DTCs with the HDS.
DTC Description
DTC
Freeze Frame
68-12 Brake Pedal Position Switch Stuck ON
    

Is DTC 68-12 indicated?

     
YES
     
     
     
Go to step 7.
     
NO
     
     
     
If the PCM was updated, troubleshooting is complete. If the PCM was substituted, replace the original PCM.?
7.
VSA modulator-control unit check (update):

VSA modulator-control unit check (update)
?1.
Update the VSA modulator-control unit if it does not have the latest software.

?2.
Turn the ignition switch to LOCK (0), then turn it to ON (II) again, or select the OFF mode, then the ON mode.

?3.
Check for DTCs with the HDS.
DTC Description
DTC
Freeze Frame
     

Is DTC 68-12 indicated?

     
YES
     
     
     
Check for loose terminals in the VSA modulator-control unit 21P connector. If the VSA modulator-control unit was updated and the symptom/indication is still present, replace the VSA modulator-control unit.?
     
NO
     
     
     
Troubleshooting is complete. If any other DTCs are indicated, go to the indicated DTCs troubleshooting.?