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Check Vehicle Signals With Line Diag Mode

Turn the ignition switch to ACC.
Press the button (b) twice with the button (a) pressed.

Fig 1: Identifying Button
Courtesy of SUBARU OF AMERICA, INC.

NOTE: Pressing the button (c) for 3 seconds or more, or turning the ignition switch from the OFF to ACC position can exit the diagnostic mode.
{Line Diag} screen is displayed.
Check the connection status with the {Vehicle Signal Check} in the {Line Diag} screen.

Fig 2: Screen Display - Connection Status
Courtesy of SUBARU OF AMERICA, INC.

NOTE: GPS is displayed only for the navigation system.

Check illumination
NOTE: Make sure that the bright switch is not ON.
1. Turn the ignition to ON.
2. Set the lighting switch to the parking position.
3. Make sure that {ON} lights in ILL+ and then the screen becomes dim.
  ON: Normal
  
  OFF: Abnormal Check the signal line connector. If there are no problems, the unit could be faulty.
Check speed sensor
NOTE:
- Before starting inspections, check the safety around the vehicle.
- Lift up the vehicle as necessary.
- When the diagnostic trouble code is input in the VDC control module, perform the Clear Memory operation.
1. Drive the vehicle at 9 km/h (6 MPH) or more.
2. Check that {ON} is displayed in SPD.
  ON: Normal
  
  OFF: Vehicle speed is less than 7 km/h (4 MPH), or malfunction is detected in the signal line. Check the signal line connector. If there are no problems, the unit could be faulty.
Check parking brake signal
1. Pull the parking brake switch.
2. Check that {ON} is displayed in PKB.
  ON: Normal
  
  OFF: Abnormal Check the signal line connector. If there are no problems, the unit could be faulty.
Check back sensor
NOTE: Before starting inspections, check the safety behind the vehicle.
1. Turn the ignition to ON.
2. Pull the parking brake switch and depress the brake pedal, then place the select lever or gear shift lever in reverse.
3. Make sure that {OK} is displayed in REV.
  ON: Normal
  
  OFF: Abnormal Check the signal line connector. If there are no problems, the unit could be faulty.