Pinpoint Test A: No Power In All Ignition Switch Positions

WARNING: This page is about a different car, the 2010 Lincoln MKX and 2010 Ford Edge. However, it is still accessible from the selected car via links, so may be relevant.

NOTE: Use the Flex Probe Kit for all test connections to prevent damage to the wiring terminals. Do not use standard multi-meter probes.

NOTE: Verify that battery voltage is 10 volts or greater.

A1 CHECK FOR VOLTAGE AT SJB FUSE 27 (20A)
- Ignition OFF.
- Disconnect: SJB Fuse 27 (20A).
- Measure the voltage between SJB fuse 27 (20A), input side and ground.
- Is the voltage greater than 10 volts?
- Yes: GO to A2 .
- No: GO to A3.
A2 CHECK FOR VOLTAGE ON CIRCUIT SBP27 (BU/RD)
- Connect: SJB Fuse 27 (20A).
- Disconnect: Ignition Switch C250.
- Measure the voltage between ignition switch C250-4, circuit SBP27 (BU/RD), harness side and ground.
  
  Fig 1: Measuring Voltage Between Ignition Switch C250-4, Circuit SBP27 (BU/RD), Harness Side And Ground
  Courtesy of FORD MOTOR CO.
- Is the voltage greater than 10 volts?
- Yes: INSTALL a new ignition switch. REFER to IGNITION SWITCH . TEST the system for normal operation.
- No: VERIFY SJB fuse 27 (20A) is OK. If OK, REPAIR circuit SBP27 (BU/RD). If not OK, REFER to the SYSTEM WIRING DIAGRAMS for Edge or SYSTEM WIRING DIAGRAMS for MKX to identify the possible causes of the circuit short. TEST the system for normal operation.
A3 CHECK FOR CORRECT SJB OPERATION
- Disconnect: SJB C2280A.
- Disconnect: SJB C2280B.
- Check the SJB connectors for:
  - corrosion.
  - pushed-out pins.
  - spread terminals.
- Connect: SJB C2280A.
- Connect: SJB C2280B.
- Make sure the connectors seat correctly, then operate the system and verify the concern is still present.
- Is the concern still present?
- Yes: INSTALL a new SJB . REFER to MULTIFUNCTION ELECTRONIC MODULES . TEST the system for normal operation.
- No: The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector.