Pinpoint Test B: DTC C1094/C1782: PARK BRAKE APPLY/RELEASE SWITCH CIRCUIT FAILURE

WARNING: This page is about a different car, the 2005 Lincoln LS. However, it is still accessible from the selected car via links, so may be relevant.

CAUTION: Use the Flex Probe Kit for all test connections to prevent damage to the wiring terminals. Do not use standard multimeter probes.

B1 CHECK THE ELECTRONIC PARKING BRAKE (EPB) SWITCH
- Disconnect the battery. Refer to CHARGING SYSTEM - GENERAL INFORMATION .
- Disconnect: EPB Switch C3218.
- Measure the resistance between EPB switch C3218 pin 8, component side and C3218 pin 5, component side while the EPB switch is in the idle position; and between the EPB switch C3218 pin 4, component side and C3218 pin 5, component side while the EPB switch is in the idle position.
  
  Fig 1: Measuring Electronic Parking Brake (EPB) Switch Resistance
  Courtesy of FORD MOTOR CO.
- Measure the resistance between the EPB switch C3218 pin 8, component side and C3218 pin 5, component side while the EPB switch is in the apply position; and between the EPB switch C3218 pin 4, component side and C3218 pin 5, component side while the EPB switch is in the release position.
- Is the resistance between 149 - 153 ohms in the apply position and between 597 - 609 ohms in the idle position?
- Yes : GO to B2.
- No : INSTALL a new parking brake. REFER to PARKING BRAKE SWITCH in this article . CLEAR the DTCs. REPEAT the self-test. RESET the EPB system. REFER to Electronic Parking Brake (EPB) Resetting in this article .
B2 CHECK CIRCUIT 8-CG15 (WH/BU) FOR A SHORT TO VOLTAGE
- Measure the voltage between the EPB switch C3218-8, circuit 8-CG15 (WH/BU), harness side and ground.
  
  Fig 2: Measuring Voltage Between EPB Switch C3218-8, Circuit 8-CG15 (WH/BU), Harness Side And Ground
  Courtesy of FORD MOTOR CO.
- Is battery voltage present
- Yes : REPAIR the circuit. CLEAR the DTCs. RESET the EPB module. REFER to ELECTRONIC PARKING BRAKE (EPB) RESETTING in this article . REPEAT the self-test.
- No : GO to B3.
B3 CHECK CIRCUIT 8-CG15 (WH/BU) FOR AN OPEN
- Disconnect: EPB Module C4205b.
- Measure the resistance between the EPB module C4205b-5, circuit 8-CG15 (WH/BU), harness side and the EPB switch C3218-8, circuit 8-CG15 (WH/BU), harness side.
  
  Fig 3: Measuring Resistance Between EPB Module C4205b-5, Circuit 8-CG15 (WH/BU), Harness Side And EPB Switch C3218-8, Circuit 8-CG15 (WH/BU), Harness Side
  Courtesy of FORD MOTOR CO.
- Is the resistance less than 5 ohms
- Yes : GO to B4.
- No : REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test. RESET the EPB system. REFER to ELECTRONIC PARKING BRAKE (EPB) RESETTING in this article .
B4 CHECK CIRCUIT 10-CG15 (GY/VT) FOR A SHORT TO VOLTAGE
- Measure the voltage between the EPB switch C3218-4, circuit 10-CG15 (GY/VT), harness side and ground.
  
  Fig 4: Measuring Voltage Between EPB Switch C3218-4, Circuit 10-CG15 (GY/VT), Harness Side And Ground
  Courtesy of FORD MOTOR CO.
- Is battery voltage present
- Yes : REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test. RESET the EPB system. REFER to ELECTRONIC PARKING BRAKE (EPB) RESETTING in this article .
- No : GO to B5
B5 CHECK CIRCUIT 10-CG15 (GY/VT) FOR AN OPEN
- Measure the resistance between the EPB module C4205b-6 circuit 10-CG15 (GY/VT), harness side and the EPB switch C3218-4 circuit 10-CG15 (GY/VT), harness side.
  
  Fig 5: Measuring Resistance Between EPB Module C4205b-6 Circuit 10-CG15 (GY/VT), Harness Side And EPB Switch C3218-4 Circuit 10-CG15 (GY/VT), Harness Side
  Courtesy of FORD MOTOR CO.
- Is the resistance less than 5 ohms
- Yes : INSTALL a new EPB module. REFER to PARKING BRAKE MODULE in this article . REPEAT the self-test. RESET the EPB system. REFER to Electronic Parking Brake (EPB) Resetting in this article .
- No : REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test. RESET the EPB system. REFER to ELECTRONIC PARKING BRAKE (EPB) RESETTING in this article .