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Home >> Buick >> 2003 >> Century Base >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls Self-Diagnostics - 3.1L Engine >> Diagnostic Tests >> DTC P0650: Mil Control Circuit >> Circuit Description
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Circuit Description

The Malfunction Indicator light (MIL) is located on the Instrument Panel Cluster (IPC). The MIL informs the driver that an emission system fault has occurred and that the engine control system requires service. The Powertrain Control Module (PCM) monitors the MIL control circuit for conditions that are incorrect for the commanded state of the MIL. For example, a failure condition exists if the PCM detects low voltage when the MIL is commanded OFF, or high voltage when the MIL is commanded ON. If the PCM detects an improper voltage on the MIL control circuit, DTC P0650 will set.