Engine Oil Life

Engine oil life left % is based on the information it receives from an UART message from the PCM. The DIC displays the current % of the GM Oil Life System. When the oil needs changing, the CHANGE OIL SOON indicator in the DIC turns on. The BCM will sound an audible warning with this indicator on. When the engine oil is changed the CHANGE OIL SOON indicator needs to be cleared out of the DIC and the oil life left needs to be reset. Refer to GM Oil Life System - Resetting in Maintenance and Lubrication. The value of this mode is retained during ignition OFF. If the engine oil life does not appear in the DIC there is a problem with the UART serial data line. Refer to Scan Tool Does Not Communicate with UART Data Line in Data Link Communications.