DTC P0650: Malfunction Indicator Light Control Circuit: Description

Ignition voltage is supplied directly to the Malfunction Indicator Light (MIL). The Powertrain Control Module (PCM) controls the MIL by grounding the control circuit via an internal solid state device called a driver. The primary function of the driver is to supply the ground circuit. Each driver has a fault line which is monitored by the PCM. When the PCM is commanding a component on, voltage of the control circuit should be near zero volts. When the PCM is commanding a component off, voltage potential of the circuit should be near battery voltage. If the fault detection circuit senses a voltage other than what is expected, Diagnostic Trouble Code (DTC) will set.