Engine Starting

Engine Starting

Crank request Signal

The crank request signal is continually monitored for the presence of a signal whilst the vehicle is in motion. Vehicle motion is confirmed by checking vehicle speed, engine speed and engine load. If the crank request signal is detected for longer than the defined time a failure is registered.

Park / Neutral Switch

During the engine crank operation if the park / neutral input is low, with the CAN signal from the transmission indicating park / neutral is selected; the low fault timer is enabled. When the low fault timer reaches the calibrated time, the low fault flag is set.

If the park / neutral input is high, and the vehicle is detected as moving with an appropriate engine load, then the high fault timer will be enabled. When the high fault timer reaches the calibrated time, the high fault flag is set.

Starter relay

The starter relay is controlled by the ECM in response to a valid crank request signal when the vehicle is stationary and park neutral is selected. A failure of the starter relay circuit will be registered if the starter relay drive signal from the ECM is on but the starter relay feedback indicates that the relay is off.