Pinpoint Test A: The Ignition Switch Is Inoperative

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

A1 CHECK THE IGNITION SWITCH FOR POWER.
- Key in OFF position.
- Disconnect: Ignition Switch C250.
- Measure the voltage between ignition switch C250-4, circuit 1715 (RD), harness side and ground.
  
  Fig 1: Checking Ignition Switch For Power
- Is the voltage greater than 10 volts?
Yes : GO to A2.

No : VERIFY BJB fuse 1 (50A) and SJB fuse 4 (10A) are OK. If OK, GO to A3.
A2 CHECK THE IGNITION SWITCH
- Carry out the Ignition Switch Component Test. Refer to IGNITION SWITCH for gasoline models or IGNITION SWITCH for hybrid models .
- Is the ignition switch OK?
Yes : GO to A4.

No : INSTALL a new ignition switch. REFER to IGNITION SWITCH . CLEAR the DTCs. REPEAT the self-test.
A3 CHECK CIRCUIT 1715 (RD) FOR AN OPEN
- Disconnect: SJB C2280a.
- Measure the resistance between ignition switch C250-4 circuit 1715 (RD), harness side and SJB C2280a-6 circuit 1715 (RD), harness side.
  
  Fig 2: Checking Circuit 1715 (RD) For An Open
- Is the resistance less than 5 ohms?
Yes : GO to A4.

No : REPAIR circuit 1715 (RD) for an open. CLEAR the DTCs. REPEAT the self-test.
A4 CHECK FOR CORRECT SJB OPERATION
- Disconnect all the SJB connectors.
- Check for:
  - corrosion.
  - pushed-out pins.
- Connect all the SJB connectors and make sure they seat correctly.
- Operate the system and determine if the concern is still present.
- Is the concern still present?
Yes : INSTALL a new SJB. REFER to MULTIFUNCTION ELECTRONIC MODULES .

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.