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 Diagrams Set 13, Power Distribution 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 the SJB and the Battery Junction Box (BJB) depending on ignition switch position. The ignition switch has 4 possible states:

- OFF - Power on key-in ignition circuit CDC30 (BU/GY) when the ignition key is inserted into the ignition switch. If the key is not in the ignition switch, then there will be no power on circuit CDC30 (BU/GY).
- ACC - Power on circuit CDC33 (VT/GN).
- RUN - Power on circuit CDC32 (BN/YE).
- START - Power on circuit CDC35 (BU/WH).

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 THE VOLTAGE TO THE IGNITION SWITCH


- Disconnect: Ignition Switch C250.
- Measure the voltage between the ignition switch C250-4, circuit SBP27 (BU/RD), and ground.




- Is the voltage greater than 10 volts?

Yes
GO to A2.

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.

-------------------------------------------------
A2 CHECK THE IGNITION SWITCH


- Carry out the Ignition Switch - Electrical Component Test.
- Is the ignition switch OK?

Yes
GO to A3.

No
INSTALL a new ignition switch. REFER to Ignition Switch Ignition Switch. TEST the system for normal operation.

-------------------------------------------------
A3 CHECK FOR CORRECT SJB OPERATION


- Disconnect: All SJB Connectors.
- Check the SJB connectors for:
- corrosion.
- pushed-out pins.
- spread terminals.
- Connect: All SJB Connectors.
- 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. 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.

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