Ignition/Crank Signal

The Powertrain Control Module (PCM) receives 3 ignition inputs from the ignition switch: ignition 0 signal, ignition 1 signal, and crank signal. The PCM receives the ignition 0 signal with the ignition switch in the CRANK position. The ignition switch sends this signal through the Off/Run/Crank voltage circuit. The PCM uses a Class 2 ignition mode message and voltage input from separate systems to test the Off/Run/Crank voltage circuit. If the PCM detects an improper ignition 0, 1 or crank signal, a related Diagnostic Trouble Code (DTC) will set. If these signals are intermittent or not available, hard starting or a no-start condition may result.