ECM Monitored Systems

The ECM can detect certain problems in the electrical system.

Open or Shorted Circuit  - The ECM will not distinguish between an open or a short to ground, however the ECM can determine if there is excessive current on a circuit, such as a short to voltage or a decrease in component resistance.

Output Device Current Flow  - The ECM senses whether the output devices are electrically connected.

If there is a problem with the circuit, the ECM senses whether the circuit is open, shorted to ground (-), or shorted to (+) voltage.

Fuel Pressure:  Fuel pressure is controlled by the fuel injection pump and fuel pressure solenoid. The ECM uses a fuel pressure sensor to determine if a fuel pressure problem exists.

Fuel Injector Malfunctions:  The ECM can determine if a fuel injector has an electrical problem. The fuel injectors on the diesel engine are controlled  by the ECM.