Pinpoint Test G: DTC C1748 Switch Input Circuit Short To Ground

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.

CAUTION: Use the correct probe adaptor(s) when making measurements. Failure to use the correct probe adaptor(s) may damage the connector.

G1 CHECK FOR RECORDED DTCS FROM BOTH THE CONTINUOUS AND ON-DEMAND PARKING AID MODULE SELF-TESTS
- Check for recorded parking aid module DTCs from the continuous and on-demand self-tests.
- Are any parking aid module DTCs recorded?
Yes : If DTC C1748, GO to G2.

All other DTCs, REFER to the PARKING AID MODULE DIAGNOSTIC TROUBLE CODE (DTC) INDEX .

No : GO to PINPOINT TEST B .
G2 CHECK THE PARKING AID DISABLE SWITCH OPERATION
- Key in OFF position.
- Disconnect: Parking Aid Module C4014.
- While pressing and releasing the parking aid disable switch, measure the resistance between the parking aid module C4014-11, circuit 1435 (DG/VT), harness side and ground.
  
  Fig 1: Checking Parking Aid Disable Switch Operation
  Courtesy of FORD MOTOR CO.
- Is the resistance less than 5 ohms with the switch pressed and greater than 10,000 ohms with the switch released?
Yes : GO to G4.

No : GO to G3.
G3 CHECK CIRCUIT 1435 (DG/VT) FOR A SHORT TO GROUND
- Disconnect: Parking Aid Disable Switch C2339.
- Measure the resistance between the parking aid module C4014-11, circuit 1435 (DG/VT), harness side and ground.
  
  Fig 2: Checking Circuit 1435 (DG/VT) For A Short To Ground
  Courtesy of FORD MOTOR CO.
- Is the resistance greater than 10,000 ohms?
Yes : INSTALL a new switch. REFER to PARKING AID SWITCH . TEST the system for normal operation.

No : REPAIR the circuit. TEST the system for normal operation.
G4 CHECK FOR CORRECT PARKING AID MODULE OPERATION
- Disconnect the parking aid module connector.
- Check for:
  - corrosion
  - pushed-out pins
- Connect the parking aid module connector and make sure it seats correctly.
- Operate the system and verify the concern is still present.
- Is the concern still present?
Yes : INSTALL a new parking aid module. REFER to PARKING AID MODULE . CLEAR the DTCs. REPEAT the self-test. CARRY OUT the diagnostic tool data link test.

No : The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. CLEAR the DTCs. REPEAT the self-test.