Normal Operation and Fault Conditions
Refer to MIL .
If the engine MIL request message is missing or invalid for less than 5 seconds, the IPC defaults the MIL to its last state (on or off), based upon the last known good message received.
If the engine MIL request message is missing for 5 seconds or longer, the BCM and the IPC set DTC U0100:00. If the engine MIL request message is missing, the IPC defaults the MIL on.