Pinpoint Test BG: DTC U300A:62 Or DTC U300A:64
Instrumentation, Message Center and Warning Chimes
Pinpoint Test BG: DTC U300A:62 Or DTC U300A:64
Normal Operation
With the ignition switch in the START or RUN position, the Instrument Panel Cluster (IPC) receives voltage from the Smart Junction Box (SJB) through the voltage input circuit. The IPC (Instrument Panel Cluster) also receives a networked ignition status from the SJB (Smart Junction Box) over the Medium Speed Controller Area Network (MS-CAN) communication bus.
- DTC U300A:62 (Ignition Switch: Signal Compare Failure)- the IPC (Instrument Panel Cluster) compares the networked input with the hardwired input and sets DTC U300A:62 in continuous memory and on-demand if a discrepancy is detected.
- DTC U300A:64 (Ignition Switch: Signal Plausibility Failure)- the IPC (Instrument Panel Cluster) monitors the messaged START status and sets DTC U300A:64 in continuous memory and on-demand if the IPC (Instrument Panel Cluster) detects a START input for 15 seconds. Once the fault condition is detected, the IPC (Instrument Panel Cluster) retains limited functionality for 15 seconds then returns to full functionality.
This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- SJB (Smart Junction Box)
PINPOINT TEST BG : DTC U300A:62 OR DTC U300A:64
NOTICE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.
BG1 CHECK THE IPC (Instrument Panel Cluster) RUN/START VOLTAGE SUPPLY
- Ignition OFF.
- Disconnect: IPC (Instrument Panel Cluster) C220.
- Measure the voltage between the IPC (Instrument Panel Cluster) C220-20, circuit CBP29 (WH/VT), harness side and ground.
- Ignition ON.
- Measure the voltage between the IPC (Instrument Panel Cluster) C220-20, circuit CBP29 (WH/VT), harness side and ground.
- Place the ignition in the START position.
- Measure the voltage between the IPC (Instrument Panel Cluster) C220-20, circuit CBP29 (WH/VT), harness side and ground.
Is the voltage 0 volts in the OFF position and greater than 10 volts in the RUN and START positions?
Yes
GO to BG2.
No
VERIFY the SJB (Smart Junction Box) fuse 29 (5A) is OK. If OK, REPAIR the circuit for an open. TEST the system for normal operation. If not OK, Refer to the Wiring Diagrams to identify the possible causes for the circuit short. Electrical Diagrams
BG2 CHECK THE SJB (Smart Junction Box) INPUT PIDs FROM THE IGNITION SWITCH
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: SJB (Smart Junction Box) DataLogger.
- Select the SJB (Smart Junction Box) PIDs ignition ACC (IGN_A_ECU), ignition OFF (IGN_O_ECU), ignition RUN (IGN_R_ECU), and ignition START (IGN_S_ECU). Monitor the ignition PIDs while switching the ignition from ACC, OFF, RUN and START.
Do the SJB (Smart Junction Box) PIDs match the ignition mode?
Yes
GO to BG3.
No
REFER to Steering Column to diagnose the ignition outputs to the SJB (Smart Junction Box).
BG3 CHECK THE IPC (Instrument Panel Cluster) DTCs
- Enter the following diagnostic mode on the scan tool: IPC (Instrument Panel Cluster) Self-Test.
- Repeat the IPC (Instrument Panel Cluster) self-test. Clear the DTCs.
Is DTC U300A:62 or DTC U300A:64 still present?
Yes
INSTALL a new SJB (Smart Junction Box). CLEAR the DTCs. REPEAT the self-test.
If the DTC is still present, INSTALL a new IPC (Instrument Panel Cluster). REFER to Instrument Panel Cluster (IPC) . TEST the system for normal operation.
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.