Pinpoint Test A: No Power in All Ignition Switch Positions

Steering Column Switches

Pinpoint Tests

Pinpoint Test A: No Power in All Ignition Switch Positions

Refer to Wiring Diagram Set 13 (Escape/Mariner, Escape Hybrid/Mariner Hybrid), Power Distribution/SJB for schematic and connector information. Diagrams By Number

Normal Operation

The ignition switch receives fused battery voltage along circuit SBP27 (BU/RD) from Smart Junction Box (SJB) fuse 27 (20A). The ignition switch then sends that voltage out to various systems depending on ignition switch position. The ignition switch has 4 possible states:

- OFF - No power on any circuits
- ACC - Power on circuit CDC33 (VT/GN)
- RUN - Power on circuits CDC33 (VT/GN) and CDC34 (WH/OG)
- START - Power on circuit CDC34 (WH/OG), CDC35 (BU/WH) and CDC54 (WH/GN) (non-hybrid vehicles)

This pinpoint test is intended to diagnose the following:
- Fuse
- Wiring, terminals or connectors
- Ignition switch
- SJB




PINPOINT TEST A: NO POWER IN ALL IGNITION SWITCH POSITIONS

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

-------------------------------------------------
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
INSTALL a new SJB. REFER to Body Control Systems. TEST the system for normal operation.

-------------------------------------------------
A2 CHECK FOR VOLTAGE TO THE IGNITION SWITCH



- 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.




- Is the voltage greater than 10 volts?

Yes
INSTALL a new ignition switch. REFER to Ignition Switch 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 Wiring Diagrams to identify the possible causes of the circuit short. TEST the system for normal operation. Diagrams By Number

-------------------------------------------------