Pinpoint Test A: The Shift Interlock System Does Not Release Or Lock Correctly

WARNING: This page is about a different car, the 2006 Mercury Mariner and 2006 Ford Escape. However, it is still accessible from the selected car via links, so may be relevant.

A1 CHECK THE BRAKE PEDAL POSITION (BPP) SWITCH
- Depress the brake pedal.
- Did the stop lamps illuminate with the brake pedal depressed?
Yes : GO to A2.

No : REFER to EXTERIOR LIGHTING .
A2 CHECK FUSE F4 (10A)
- Key in OFF position.
- Check fuse: F4 (10A).
- Is the resistance less than 5 ohms?
Yes : GO to A4.

No : GO to A3.
A3 CHECK CIRCUIT 1715 (RD) FOR SHORT TO GROUND
- Key in OFF position.
- Disconnect: Ignition Switch C250.
- Disconnect: Fuse F4 (10A).
- Measure the resistance between output side of fuse F4 (10A) and ground.
  
  Fig 1: Checking Circuit 1715 (RD) For Short To Ground
- Is the resistance greater than 10,000 ohms?
Yes : GO to A6.

No : REPAIR the circuit. TEST the system for normal operation.
A4 CHECK CIRCUIT 1715 (RD) FOR AN OPEN
- Key in OFF position.
- Disconnect: Ignition Switch C250.
- Disconnect: Fuse F4 (10A).
- Measure the resistance between output side of fuse F4 (10A) and ignition switch C250-4.
  
  Fig 2: Checking Circuit 1715 (RD) For An Open
- Is the resistance less than 5 ohms?
Yes : GO to A5.

No : REPAIR the circuit. TEST the system for normal operation.
A5 CHECK THE IGNITION SWITCH
- Measure the resistance between ignition switch C250-4 and C250-5, component side with the ignition key in and with the ignition key out.
  
  Fig 3: Checking Ignition Switch
- Is the resistance less than 5 ohms with the ignition key in and greater than 10,000 ohms with the ignition key out?
Yes : GO to A7.

No : INSTALL a new ignition switch. REFER to STEERING COLUMN SWITCHES . TEST the system for normal operation.
A6 CHECK CIRCUIT 158 (BK/PK) FOR SHORT TO GROUND
- Disconnect: Smart Junction Box (SJB) C2280E.
- Measure the resistance between ignition switch C250-5 and ground.
  
  Fig 4: Checking Circuit 158 (BK/PK) For Short To Ground
- Is the resistance greater than 10,000 ohms?
Yes : INSTALL a new SJB. REFER to MULTIFUNCTION ELECTRONIC MODULES . TEST the system for normal operation.

No : REPAIR the circuit. TEST the system for normal operation.
A7 CHECK CIRCUIT 158 (BK/PK) FOR AN OPEN
- Disconnect: Smart Junction Box (SJB) C2280E.
- Measure the resistance between ignition switch C250-5 and SJB C2280E-29.
  
  Fig 5: Checking Circuit 158 (BK/PK) For An Open
- Is the resistance less than 5 ohms?
Yes : GO to A8.

No : REPAIR the circuit. TEST the system for normal operation.
A8 CHECK CIRCUIT 605 (RD) FOR SHORT TO GROUND
- Disconnect: Floor Shifter C2096.
- Disconnect: SJB C2280A.
- Measure the resistance between SJB C2280A-9 and ground.
  
  Fig 6: Checking Circuit 605 (RD) For Short To Ground
- Is the resistance greater than 10,000 ohms?
Yes : GO to A9.

No : REPAIR the circuit. TEST the system for normal operation.
A9 CHECK CIRCUIT 605 (RD) FOR AN OPEN
- Disconnect: Floor Shifter C2096.
- Disconnect: SJB C2280A.
- Measure the resistance between SJB C2280A-9 and floor shifter C2096-3.
  
  Fig 7: Checking Circuit 605 (RD) For An Open
- Is the resistance less than 5 ohms?
Yes : GO to A10.

No : REPAIR the circuit. TEST the system for normal operation.
A10 CHECK SMART JUNCTION BOX (SJB)
- Connect: Ignition Switch C250.
- Connect: SJB C2280E.
- Connect: SJB C2280A.
- Key in ON position.
- Apply the brake.
- Measure the voltage between floor shifter C2096-3 and ground.
  
  Fig 8: Checking Smart Junction Box (SJB)
- Is the voltage greater than 10 volts?
Yes : GO to A11.

No : INSTALL a new SJB. REFER to MULTIFUNCTION ELECTRONIC MODULES . TEST the system for normal operation.
A11 CHECK CIRCUIT 57 (BK) FOR AN OPEN
- Measure the resistance between floor shifter C2096-1 and ground.
  
  Fig 9: Checking Circuit 57 (BK) For An Open
- Is the resistance less than 5 ohms?
Yes : INSTALL a new brake shift interlock module. REFER to SELECTOR LEVER CABLE .

No : REPAIR the circuit. TEST the system for normal operation.