Symptoms

- Engine Light ON (or Service Engine Soon Warning Light)

Possible Causes

- Fuel level circuit open or shorted - Poor fuel level electrical connection - Faulty PCM

Description

The PCM controls the fuel gauge through the fuel gauge control circuit. The PCM supplies a pulse width modulated (PWM) duty cycle signal to control the fuel gauge. The PCM receives the fuel level information from the fuel level sensor. The PCM controls the gauge by grounding the control circuit via an internal switch called a driver. The primary function of the driver is to supply the ground for the controlled component. Each driver has a fault line which the PCM monitors. If the fault detection circuit senses a voltage other than what the PCM expects, the fault line status changes causing the DTC to set.