DTC P0719: Brake Switch "B" Circuit Low: Notes

DTC detecting condition:

Immediately at fault recognition

Trouble symptom:

Gear is not shifted down when climbing a hill or driving down a hill.

CAUTION: Use the check board when measuring the TCM terminal voltage and resistance.

Wiring diagram:

ENGINE TYPE FB
Stop light system Ref. to WIRING SYSTEM>STOP LIGHT SYSTEM .

Courtesy of SUBARU OF AMERICA, INC.
ENGINE TYPE EZ
Stop light system Ref. to WIRING SYSTEM>STOP LIGHT SYSTEM .

Courtesy of SUBARU OF AMERICA, INC.

CHECK FUSE (NO. 37) .
1. Turn the ignition switch to OFF.
2. Remove the fuse (No. 37).
3. Check the fuse.
Is the check result OK?

Yes: Go to 2 .

No: Replace the fuse (No. 37). If the new fuse (No. 37) has blown out easily, repair the short circuit of harness between fuse (No. 37) and stop light switch.
CHECK HARNESS .
1. Turn the ignition switch to OFF.
2. Disconnect the TCM connector.
3. Disconnect the stop light switch connector.
4. Measure the resistance between TCM connector and stop light switch connector.
  Connector & terminal
  
  ENGINE TYPE FB
  
  (T10) No. 29 - (B65) No. 2:
  
  ENGINE TYPE EZ
  
  (B54) No. 29 - (B65) No. 2:
Is the resistance less than 1 Ω?

Yes: Go to 3 .

No: Repair the open circuit of harness.
CHECK HARNESS .
Measure the resistance between the stop light switch connector and fuse (No. 37).

Connector & terminal

(B65) No. 1 - fuse (No. 37):

Is the resistance less than 1 Ω?

Yes: Go to 4 .

No: Repair the open circuit of harness.
CHECK INPUT SIGNAL FOR TCM .
1. Install the fuse (No. 37).
2. Connect the stop light switch connector.
3. Depress the brake pedal.
4. Measure the voltage between TCM connector and chassis ground.
  Connector & terminal
  
  ENGINE TYPE FB
  
  (T10) No. 29 (+) - Chassis ground (-):
  
  ENGINE TYPE EZ
  
  (B54) No. 29 (+) - Chassis ground (-):
Is the voltage 10 V or more?

Yes: Go to 5 .

No: Replace the stop light switch. Ref. to BRAKE>STOP LIGHT SWITCH .
CHECK INPUT SIGNAL FOR TCM .
1. Connect the TCM connector.
2. With brake pedal depressed, read the data of «Stop Light Switch» using Subaru Select Monitor.
Is "ON" displayed?

Yes: Current condition is normal. Check for poor contact in connectors or harnesses, and repair the defective part.

No: Go to 6 .
CHECK FOR POOR CONTACT .
Is there poor contact in the stop light switch input signal circuit?

Yes: Repair the poor contact.

No: Replace the TCM. Ref. to CONTINUOUSLY VARIABLE TRANSMISSION (TR580)>TRANSMISSION CONTROL MODULE (TCM) . Ref. to CONTINUOUSLY VARIABLE TRANSMISSION (TR690)>TRANSMISSION CONTROL MODULE (TCM) .