12419T Mercury COVER

Illustration 1 g01397757
Heat Exchanger System
Left Side View
(1) Engine oil temperature sensor
Illustration 2 g01397758
Heat Exchanger System
Top View
(2) Inlet air pressure sensor
(3) Inlet air temperature sensor
Illustration 3 g01397759
Heat Exchanger System
Front View
(4) Coolant temperature sensor
(5) Coolant level sensor
(6) Engine oil pressure sensor
(7) Primary speed/timing sensor
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Heat Exchanger System
Right Side View
(8) Secondary speed/timing sensor
Illustration 5 g01397765
Keel Cooled System
Top view
(5) Coolant level sensors
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Heat Exchanger
Right Side View
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Keel Cooled System
Right Side View
(9) Fuel pressure sensor
(10) Fuel temperature sensor 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 outside of the specification.Coolant Level Sensor
Note: Coolant level sensor (5) is an optional feature.The coolant level sensor monitors the level of the engine coolant. The coolant level sensor is used to detect a condition when the coolant level is low. The coolant level sensor provides information to the ECM. The output from the ECM can indicate a low coolant level through a relay or a lamp. Coolant must be added to the cooling system in order to correct the condition.The system can be programmed with one of the following options:"ENABLED" - The system will monitor the input from the coolant level sensor. The system is programmed to this value when the engine is shipped by Caterpillar."DISABLED" - The system will not monitor the input from the coolant level sensor. All of the diagnostics that are associated with the coolant level sensor will be disabled.See the Operation and Maintenance Manual, "Customer Specified Parameters" for more information about programmable options.Failure of the Coolant Level Sensor
A failure of the coolant level sensor will not cause a shutdown of the engine or any horsepower change.Coolant Temperature Sensor
Coolant temperature sensor (4) monitors engine coolant temperature. This feature is used for all engine system diagnostics with outputs from the ECM. The output of the ECM can indicate a high coolant temperature through a relay or a lamp.
Table 1
Coolant Temperature Sensor
Activation temperature for the high coolant temperature fault 103°C (217°F)
Activation temperature for the very high coolant temperature fault 106°C (229°F) Failure of the Coolant Temperature Sensor
The ECM will detect a failure of the coolant temperature sensor. The diagnostic lamp will warn the operator about the status of the coolant temperature sensor. Strategies that are related to the coolant temperature sensor will be disabled if a failure occurs. A failure of the coolant temperature sensor will not cause a shutdown of the engine or any horsepower change.Engine Oil Pressure Sensor
Engine oil pressure sensor (6) 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.
Table 2
Engine Oil Pressure Sensor
Operating range for the engine oil pressure sensor 0 to 690 kPa (0 to 100 psi) Low Oil Pressure Warning
The setpoint is dependent upon the engine speed. The fault will be active and logged only if the engine has been running for more than 15 seconds.