Engine Oil

CHANGE OIL
The IPC illuminates the CHANGE OIL indicator when the following occurs:
^ The PCM determines that the engine oil should be changed. The IPC receives a class 2 message from the PCM indicating the remaining oil life percent. The IPC illuminates the CHANGE OIL indicator when the remaining oil life is less than 11%. The IPC sends a class 2 message to the Body Control Module (BCM) indicating that the CHANGE OIL indicator is illuminated. The BCM sends a class 2 message to the radio in order to activate an audible warning.
^ The IPC performs the displays test at the start of each ignition cycle. The indicator illuminates for approximately 3 seconds.

Once the oil is changed, perform the engine oil monitor reset procedure in order to clear the CHANGE OIL indicator. Refer to GM Oil Life System - Resetting in Maintenance and Lubrication. The BCM monitors the oil life/TPM reset switch signal circuit and sends a class 2 message to the IPC indicating that the oil life/TPM reset switch is active (signal circuit is low). The IPC turns off the indicator when the IPC determines that a request to reset the oil life has been activated via the oil life/TPM reset switch. The IPC sends a class 2 message to the PCM in order to reset the oil life to 100%.