U1433-23

U1433-23-IMPLAUSIBLE IGNITION SWITCH STATUS MESSAGE RECEIVED - SIGNAL STUCK LOW





For a complete wiring diagram, refer to the Wiring Information.

Theory of Operation

The Body Control Module (BCM) monitors the hardwired ignition switch input circuit from the Radio Frequency (RF) Hub module and compares it to the ignition switch status message received over the Controller Area Network (CAN) bus.

- When Monitored:
With the ignition switch on.

- Set Condition:
The BCM detects that the hardwired ignition switch input voltage from the RF Hub module indicates that the ignition switch is in the off position, but the CAN bus message indicates that the ignition switch is the run position for more than 10 seconds.





1. CHECK FOR ACTIVE DTC

NOTE: Check to make sure the battery and charging system are operating properly. Battery and/or charging system problems may cause these DTCs to set.

NOTE: Diagnose any related Powertrain DTC(s) before continuing.

1. Turn the ignition on.
2. With the scan tool, read DTCs.

Does the scan tool display this DTC as active?

Yes

- Go To 2

No

- Test complete, the condition or conditions that originally set this DTC are not present at this time. Using the wiring diagrams as a guide, check all related splices and connectors for signs of water intrusion, corrosion, pushed out or bent terminals, and correct pin tension.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

2. CHECK THE (F20) IGNITION RUN-START OUTPUT CIRCUIT AT THE BCM




1. Turn the ignition off.
2. Disconnect the BCM E harness connector.
3. Turn the ignition on.
4. Measure the voltage between ground and the (F20) Ignition Run-Start Output circuit.

Is the voltage above 10.0 volts?

Yes

- Replace the BCM. Body Control Module - Removal.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

No

- Go To 3

3. CHECK THE (F20) IGNITION RUN-START OUTPUT CIRCUIT FOR A SHORT TO GROUND




1. Turn the ignition off.
2. Disconnect the RF Hub Module C1 harness connector.
3. Measure the resistance between ground and the (F20) Ignition Run-Start Output circuit.

Is the resistance above 10k Ohms?

Yes

- Go To 4

No

- Repair the short to ground in the (F20) Ignition Run-Start Output circuit.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

4. CHECK THE (F20) IGNITION RUN-START OUTPUT CIRCUIT FOR AN OPEN




1. Measure the resistance of the (F20) Ignition Run-Start Output circuit between the RF Hub Module C1 harness connector and the BCM E harness connector.

Is the resistance below 5.0 Ohms?

Yes

- Replace the RF Hub Module. Radio Frequency Module (RF Hub) - Removal.
- Perform the RADIO FREQUENCY HUB (RF HUB) VERIFICATION TEST. RF Hub Verification Test

No

- Repair the open in the (F20) Ignition Run-Start Output circuit.
- Perform the BODY VERIFICATION TEST. Body Verification Test.