P0600

DTC P0600

Circuit Description

The Alternative Fuels ECM communicates via the Class 2 serial data circuit. The Alternative Fuels ECM monitors this circuit for activity. If the Alternative Fuels ECM does not receive or send a message on the Class 2 circuit for 10 seconds, this DTC sets.


Conditions for Running the DTC

The ignition is ON.


Conditions for Setting the DTC

* The Alternative Fuels ECM does not receive, or send, a Class 2 message.
* The condition exists for 10 seconds.



Action Taken When the DTC Sets

* The PCM stores the DTC information into memory when the diagnostic runs and fails.
* The malfunction indicator lamp (MIL) will not illuminate.
* The PCM records the operating conditions at the time the diagnostic fails. The PCM stores this information in the Failure Records.



Conditions for Clearing the DTC

* A last test failed, or current DTC, clears when the diagnostic runs and does not fail.
* A history DTC will clear after 40 consecutive warm-up cycles, if no failures are reported by this or any other non-emission related diagnostic.
* Use a scan tool in order to clear the DTC.



Test Description

The numbers below refer to the step numbers on the diagnostic table.
2. This step determines if the condition is present.
4. This step determines if the condition affects other control modules.
5. This step determines if the condition is causing a no start.
6. This step determines if the Alternative Fuels ECM is the cause of the condition. If the scan tool displays other module information with the Alternative Fuels ECM disconnected, replace the Alternative Fuels ECM.
8. This step determines if the class 2 serial data circuit between the Alternative Fuels ECM and the splice pack is grounded. If the circuit is not grounded, refer to the information in Data Link Communications in order to diagnose the rest of the class 2 circuits and modules.
9. This step determines if a fuse that supplies voltage to the Alternative Fuels ECM is open. If a fuse is open, test the circuit and all related components for a short to ground.