Pinpoint Test A: No Power in All Ignition Switch Positions - Vehicles with an Ignition Switch

Steering Column Switches

Pinpoint Test A: No Power in All Ignition Switch Positions - Vehicles with an Ignition Switch

Refer to Wiring Diagram Set 13, Power Distribution/BCM for schematic and connector information Electrical Diagrams.

Normal Operation

The ignition switch receives fused battery voltage from Body Control Module (BCM) fuse 28 (15A). In the ACC or ON position, this voltage is sent to the BCM (Body Control Module). In the START position, this voltage is sent to both the BCM (Body Control Module) and the PCM.

When the ignition switch is cycled to the OFF/LOCK position from any other position the BCM (Body Control Module) begins a monitoring cycle. The monitoring cycle checks that the voltage supplied to the BCM (Body Control Module) from the ignition switch through the RUN/ACC, RUN/START and START circuits is delivered correctly for each ignition switch position.

- DTC U300A:01 (Ignition Switch: General Electric Failure)- The BCM (Body Control Module) continuously monitors the ignition switch position. This DTC sets if the voltage inputs to the BCM (Body Control Module) do not match the pre defined configurations for each ignition switch position.

This pinpoint test is intended to diagnose the following:

- Fuse

- Wiring, terminals or connectors

- Ignition switch

PINPOINT TEST A : NO POWER IN ALL IGNITION SWITCH POSITIONS - VEHICLES WITH AN IGNITION SWITCH

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 IGNITION SWITCH

- Ignition OFF.

- 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 . CLEAR the DTC. REPEAT the self-test. TEST the system for normal operation.

A2 CHECK FOR POWER TO THE IGNITION SWITCH

- Measure the voltage between ignition switch C250-4, circuit SBP28 (BU/RD), harness side and ground.






Is the voltage greater than 10 volts?

Yes
GO to A4.

No
VERIFY BCM (Body Control Module) fuse 28 (15A) Is OK. If OK, GO to A3. If not OK, REFER to the Wiring Diagrams to identify the possible cause of the circuit short Electrical Diagrams. CLEAR the DTC. REPEAT the self-test. TEST the system for normal operation.

A3 CHECK FOR POWER TO BCM (Body Control Module) FUSE 28 (15A)

- Measure the voltage between BCM (Body Control Module) fuse 28 (15A), circuit SBP28 (BU/RD), output cavity and ground.






Is the voltage greater than 10 volts?

Yes
REPAIR circuit SBP28 (BU/RD). CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

No
VERIFY MEGA fuse (120A) is OK. If OK, REPAIR circuit SDC02 (RD). If not OK, REFER to the Wiring Diagrams to identify the possible cause of the circuit short Electrical Diagrams. CLEAR the DTC. REPEAT the self-test. TEST the system for normal operation.

A4 CHECK THE BCM (Body Control Module) IGNITION SWITCH INPUT CIRCUITS FOR AN OPEN

- Disconnect: BCM (Body Control Module) C2280B.

- Measure the resistance between ignition switch C250, harness side and BCM (Body Control Module) C2280B, harness side as follows:

Ignition Switch Circuit BCM (Body Control Module) C250-6 CDC33 (VT/GN) C2280B-35 C250-1 CDC34 (WH/OG) C2280B-29 C250-7 CDC35 (BU/WH) C2280B-47






Are the resistances less than 5 ohms?

Yes
GO to A5.

No
REPAIR the affected circuit(s). CLEAR the DTC. REPEAT the self-test. TEST the system for normal operation.

A5 CHECK FOR CORRECT BCM (Body Control Module) OPERATION

- Disconnect all BCM (Body Control Module) connectors.

- Check the connectors for:
- corrosion

- damaged pins

- pushed-out pins


- Connect all BCM (Body Control Module) connectors and make sure they are seated correctly.

- Connect: Ignition Switch C250.

- Operate the system and verify the concern is still present.

Is the concern still present?

Yes
INSTALL a new BCM (Body Control Module). CLEAR the DTCs. REPEAT the self-test. 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. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.