Pinpoint Tests AX: DTC U2472

Instrumentation, Message Center and Warning Chimes

Pinpoint Tests

Pinpoint Test AX: DTC U2472

Refer to Wiring Diagram Set 60, Instrument Cluster for schematic and connector information. Diagrams By Number

Normal Operation

With the ignition switch in the START or RUN position, the Instrument Cluster (IC) receives voltage from the Smart Junction Box (SJB) through circuit CBP29 (WH/VT). The IC also receives a networked ignition status from the SJB over the Medium Speed Controller Area Network (MS-CAN) communication bus.

- DTC U2472 (Unexpected Ignition State) - sets in continuous memory when the IC detects a discrepancy between the hardwired voltage input and the messaged ignition state inputs from the SJB for greater than 5 seconds when the ignition switch is in the RUN position.

This pinpoint test is intended to diagnose the following:

- Fuse
- Wiring, terminals or connectors
- SJB
- IC



PINPOINT TEST AX: DTC U2472

NOTICE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.

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AX1 CHECK THE IC RUN/START VOLTAGE SUPPLY


- Ignition OFF.
- Disconnect: IC C220.
- Ignition ON.
- Measure the voltage between the IC C220-20, circuit CBP29 (WH/VT), harness side and ground.




- Is the voltage greater than 10 volts?

Yes
GO to AX2.

No
VERIFY the SJB fuse 29 (5A) is OK. If OK, REPAIR the circuit for an open. If not OK, REFER to the Wiring Diagrams to identify the possible causes of the circuit short. TEST the system for normal operation.

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AX2 CHECK THE SJB INPUT PIDs FROM THE IGNITION SWITCH


- Enter the following diagnostic mode on the scan tool: SJB DataLogger.
- Select the ignition switch ACC (IGN_A_ECU), ignition switch OFF (IGN_O_ECU), ignition switch RUN (IGN_R_ECU), and ignition switch START (IGN_S_ECU) PIDs. Monitor the ignition switch PIDs while cycling the ignition switch from ACC, OFF, RUN and START.
- Do the SJB PIDs match the ignition switch position?

Yes
GO to AX3.

No
REFER to Steering Column to diagnose the ignition switch inputs to the SJB. Testing and Inspection

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AX3 CHECK THE IC DTCs


- Enter the following diagnostic mode on the scan tool: IC Self-Test.
- Clear the DTCs. Repeat the IC self-test.
- Is DTC U2472 still present?

Yes
GO to AX4.

No
The system is operating correctly at this time. The DTC may have been set due to high network traffic or an intermittent fault condition.

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AX4 CHECK FOR CORRECT SJB OPERATION


- Disconnect all the SJB connectors.
- Check for:
- corrosion
- damaged pins
- pushed-out pins
- Connect all the SJB connectors and make sure they seat correctly.
- Operate the system and verify that the concern is still present.
- Is the concern still present?

Yes
INSTALL a new SJB. TEST the system for normal operation.

If the concern remains, REINSTALL the original SJB and GO to BB5.

No
The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector.

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AX5 CHECK FOR CORRECT IC OPERATION


- Disconnect the IC connector.
- Check for:
- corrosion
- damaged pins
- pushed-out pins
- Connect the IC connector and make sure it seats correctly.
- Operate the system and verify the concern is still present.
- Is the concern still present?

Yes
INSTALL a new IC. REFER to Instrument Cluster (IC) Instrument Cluster (IC). 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.

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