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Monitored Circuits


NOTE:
The engine controller can detect certain faults in its systems, the following is a list of the types of faults the engine controller can detect.

MONITORED CIRCUITS

Open or Shorted Circuit - The engine controller can determine if the input signal from the sensor is within its range and if the sensor circuit is open or shorted.

Output Device Current Flow - The engine controller can see if the output devices are hooked up. If a problem exists with an output devices' circuit, the engine controller can determine if it is open, shorted high, or shorted to ground.

Oxygen Sensor - Once the system has entered closed loop, the engine controller checks that the oxygen sensor is switching between rich and lean. Refer to Powertrain Management/Computers and Control Systems/Electronic Control Module/Description and Operation.