0388289 JOHNSON IMPELLER HSG.& SEAL ASSY.

Illustration 1 g00894185
Left side view of the 3054E engine
Typical example of a 3054E
(1) Electronic control module (ECM)
(2) Inlet manifold temperature sensor
(3) Boost pressure sensor
(4) Speed/timing sensor
(5) Engine oil pressure sensor
(6) Machine interface connector MIC
Illustration 2 g00915275
(7) Typical location of the voltage load protection module by the ECM
Illustration 3 g00915291
Right side view of the 3054E engine
Typical example of a 3054E engine
(8) Engine coolant temperature sensor Sensor Locations for the 3056E Engine
Illustration 4 g00894214
Left side view of the 3056E engine
Typical example of a 3056E engine
(1) Engine coolant temperature sensor
(2) Engine oil pressure sensor
(3) Speed/timing sensor
(4) Electronic control module (ECM)
Illustration 5 g00912351
(5) Typical location of the voltage load protection module behind the ECM
Illustration 6 g00912359
Right side view of the 3056E engine
(6) Boost pressure sensor
(7) Inlet manifold temperature sensor Alarm Lamps (Diagnostic and Warning)
Installation of both a warning lamp and a diagnostic lamp is strongly recommended in order to alert the operator of problems that may be detected by the ECM.The warning lamp will come ON for five seconds when the ECM is first turned ON in order to indicate that the lamp circuit is functional.Failure of Sensors
All Sensors
A failure of any of the sensors may be caused by one of the following malfunctions:
Sensor output is open.
Sensor output is shorted to "- battery" or "+ battery".
Measured reading of the sensor is out of specification.Programmable Monitoring System (PMS)
The Programmable Monitoring System determines the level of action that is taken by the ECM in response to a condition that can damage the engine. These conditions are identified by the ECM from the signals that are produced from the following sensors.
Boost pressure sensor
Engine oil pressure sensor
Inlet air temperature sensor
Engine coolant temperature sensor
Engine speed/timing sensors
Throttle position sensor
Fuel temperature sensorRefer to the Troubleshooting Guide for more information about sensors.Boost Pressure Sensor
The boost pressure sensor provides a signal which corresponds to boost pressure to the ECM. The ECM can control injection timing and the amount of fuel that is injected. When the throttle is increased and when the engine demands more fuel, the fuel limit is controlled in order to reduce overall smoke levels of the engine exhaust.Engine Oil Pressure Sensor
The engine oil pressure sensor is an absolute pressure sensor that measures the engine oil pressure in the main oil gallery. The engine oil pressure sensor detects engine oil pressure for diagnostic purposes. The engine oil pressure sensor sends a signal to the ECM.Inlet Air Temperature Sensor
The inlet air temperature sensor measures the inlet air temperature. A signal is sent to the Electronic Control Module (ECM). The inlet air temperature sensor is also used by the ECM to determine initiation of the Cold Start Strategy.Coolant Temperature Sensor
The coolant temperature sensor monitors the engine coolant temperature. The output of the ECM can indicate a high coolant temperature through a relay or a lamp. The coolant temperature sensor is used by the ECM to determine initiation of the Cold Start Condition.Speed/Timing Sensor
If the ECM does not receive a signal from the primary speed/timing sensor the "DIAGNOSTIC" lamp will indicate a diagnostic fault code which will be logged in the ECM memory. If the ECM does not receive a signal from the primary speed/timing sensor, the ECM will read the signal from the secondary speed/timing sensor. The ECM continually checks in order to determine if there is a signal from both sensors. If either sensor fails, the faulty sensor should be replaced.Intermittent failure of the sensors will cause erratic engine control.Throttle Position Sensor
The throttle position sensor (TPS) eliminates the mechanical throttle and governor linkages. The TPS interprets the position of the throttle lever into an electrical signal that is sent to the ECM. The throttle position signal and the engine speed/timing signal are processed by the ECM in order to precisely control engine speed.