Pinpoint Test A: No Power in All Ignition Switch Positions
Steering Column Switches
Pinpoint Test A: No Power in All Ignition Switch Positions
Refer to Wiring Diagram Set 13, Power Distribution/SJB for schematic and connector information. Diagrams By Number
Normal Operation
The Battery Junction Box (BJB) receives battery voltage along circuit SDC02 (RD) and distributes this voltage to various fuses. The ignition switch receives fused battery voltage from Smart Junction Box (SJB) fuse 27 (20A) along circuit SBP27 (BU/RD). The ignition switch distributes power from circuit SBP27 (BU/RD) to one of 3 circuits depending on the ignition switch position. The ignition switch positions are:
- OFF
- ACC- Power on circuit CDC33 (VT/GN) to the SJB (Smart Junction Box)
- RUN- Power on circuit CDC01 (GN/VT) to the SJB (Smart Junction Box) and BJB (Battery Junction Box)
- START- Power on circuit CDC35 (BU/WH) to the SJB (Smart Junction Box), BJB (Battery Junction Box) and PCM
This pinpoint test is intended to diagnose the following:
- Fuse
- Wiring, terminals or connectors
- Ignition switch
- BJB (Battery Junction Box)
- SJB (Smart Junction Box)
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 ISOLATE THE IGNITION SWITCH
- Disconnect: Ignition Switch C250.
- Carry out the ignition switch component test.
Is the ignition switch OK?
Yes
GO to A2.
No
INSTALL a new ignition switch. REFER to Ignition Switch . TEST the system for normal operation.
A2 CHECK FOR POWER TO THE IGNITION SWITCH
- Measure the voltage between ignition switch C250-4, circuit SBB27 (BU/RD), harness side and ground.
Is the voltage greater than 10 volts?
Yes
The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. TEST the system for normal operation.
No
GO to A3.
A3 CHECK THE IGNITION SWITCH INPUT CIRCUIT FOR AN OPEN
- Disconnect: SJB (Smart Junction Box) Fuse 27 (20A).
- Measure the resistance between ignition switch C250-4, circuit SBB27 (BU/RD), harness side and SJB (Smart Junction Box) fuse 27 (20A), output side.
Is the resistance less than 5 ohms?
Yes
GO to A4.
No
VERIFY SJB (Smart Junction Box) fuse 27 (20A) is OK.
If OK, REPAIR circuit SBB27 (BU/RD). TEST the system for normal operation.
If not OK, GO to A7.
A4 CHECK THE IGNITION SWITCH INPUT CIRCUIT FOR A SHORT TO GROUND
- Measure the resistance between ignition switch C250-4, circuit SBB27 (BU/RD), harness side and ground.
Is the resistance greater than 10,000 ohms?
Yes
GO to A5.
No
REPAIR circuit SBB27 (BU/RD). TEST the system for normal operation.
A5 CHECK FOR POWER TO SJB (Smart Junction Box) FUSE 27 (20A)
- Measure the voltage between SJB (Smart Junction Box) fuse 27 (20A), input side and ground.
Is the voltage greater than 10 volts?
Yes
The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. TEST the system for normal operation.
No
GO to A6.
A6 CHECK FOR POWER TO THE SJB (Smart Junction Box) FUSE 18 (20A)
- Disconnect: SJB (Smart Junction Box) Fuse 18 (20A).
- Measure the voltage between SJB (Smart Junction Box) fuse 18 (20A), input side and ground.
Is the voltage greater than 10 volts?
Yes
GO to A10.
No
GO to A7.
A7 CHECK FOR POWER TO THE SJB (Smart Junction Box)
- Disconnect: SJB (Smart Junction Box) C2280G.
- Measure the voltage between SJB (Smart Junction Box) C2280G-1, circuit SBB01 (RD), harness side and ground.
Is the voltage greater than 10 volts?
Yes
INSTALL a new SJB (Smart Junction Box) fuse 27 (20A).
No
GO to A8.
A8 CHECK THE SJB (Smart Junction Box) B+ INPUT CIRCUIT FOR AN OPEN
- Disconnect: BJB (Battery Junction Box) Fuse 1 (80A).
- Disconnect: BJB (Battery Junction Box) Fuse 2 (80A).
- Measure the resistance between BJB (Battery Junction Box) fuse 1 (80A), output side and SJB (Smart Junction Box) C2280G-1, circuit SBB01 (RD), harness side.
- Measure the resistance between BJB (Battery Junction Box), fuse 2 (80A), output side and SJB (Smart Junction Box) C2280G-1, circuit SBB01 (RD), harness side.
Are the resistances less than 5 ohms?
Yes
GO to A9.
No
REPAIR circuit SBB01 (RD). TEST the system for normal operation.
A9 CHECK FOR POWER TO THE BJB (Battery Junction Box)
- Measure the voltage at BJB (Battery Junction Box) fuse 1 (80A) input side and ground.
Is the voltage greater than 10 volts?
Yes
INSTALL a new SJB (Smart Junction Box) fuse 27 (20A).
No
VERIFY BJB (Battery Junction Box) fuses 1 (80A) and 2 (80A) are OK. If OK, REPAIR circuit SDC02 (RD).
If a fuse is 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
A10 CHECK FOR CORRECT SJB (Smart Junction Box) OPERATION
- Disconnect all SJB (Smart Junction Box) connections.
- Check the SJB (Smart Junction Box) connections for:
- corrosion.
- pushed-out pins.
- spread terminals.
- Connect the SJB (Smart Junction Box) connections and make sure they are seated correctly.
- Operate the system and verify the concern is still present.
Is the concern still present?
Yes
INSTALL a new SJB (Smart Junction Box). CLEAR the DTCs. 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. TEST the system for normal operation.