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ECM Monitored Systems

WARNING: This page is about a different car, the 2009 Jeep Grand Cherokee. However, it is still accessible from the selected car via links, so may be relevant.

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.