Perkins 1200 Series Marine Auxiliar Engines Troubleshoting Guide

Electronic Troubleshooting
Welding Precaution Correct welding procedures are necessary in order to avoid damage to the following components:

1. Electronic Control Module (ECM) on the engine
2. Sensors
3. Associated components

Components for the driven equipment shouldalso be considered. When possible, remove the component that requires welding. When weldingon an engine that is equipped with an ECMand removal of the component is not possible,the following procedure must be followed. This procedure minimizes the risk to the electronic components.

1. Stop the engine. Remove the electrical power from the ECM.
2. Ensure that the fuel supply to the engine is turned off.
3. Disconnect the negative battery cable from the battery. If a battery disconnect switch is installed,open the switch.

Rated Fuel Limit: This limit is based on the power rating of the engine and on the engine rpm. The Rated Fuel Limit enables the engine power and torque outputs to conform to the power and torque curves of a specific engine model. These limits arein the flash file and these limits cannot be changed.

Reference Voltage: Reference voltage is a regulated voltage and a steady voltage that is supplied by the ECM to a sensor. The reference voltage is used by the sensor to generate a signal voltage.

Relay: A relay is an electromechanical switch. A flow of electricity in one circuit is used to control the flow of electricity in another circuit. A small currentor voltage is applied to a relay in order to switch a much larger current or voltage.

Secondary Speed/Timing Sensor: This sensor determines the position of the camshaft during engine operation. If the primary speed/timing sensor fails during engine operation, the secondary speed/timing sensor is used to provide the signal.

Sensor: A sensor is a device that is used to detect the current value of pressure or temperature, or mechanical movement. The information that is detected is converted into an electrical signal.

Short Circuit: A short circuit is a condition that has an electrical circuit that is inadvertently connected to an undesirable point. An example of a short circuitis a wire which rubs against a vehicle frame andthis rubbing eventually wears off the wire insulation.Electrical contact with the frame is made and a short circuit is created.

Signal: The signal is a voltage or a waveform that is used in order to transmit information typically from a sensor to the ECM.
Suction Control Valve (SCV): The SCV is a control device in the high-pressure fuel pump. The ECM controls the pressure in the fuel rail by using the SCV to control the amount of fuel that enters the chambers in the pump.