TRANSMISSION 3P9205 - Caterpillar

Coolant Temperature Sensor
The coolant temperature sensor (5) monitors engine coolant temperature. This feature is used for engine system diagnostics with an output from the Electronic Control Module (ECM). The output of the ECM can indicate a high coolant temperature through a relay or a lamp. In addition, the sensor activates the cold start strategy which improves the startability of the engine.The minimum coolant temperature that will activate the alarm is 106°C (223°F). The switch opens as the coolant cools. A resetting procedure is not required.Failure of the Coolant Temperature Sensor
If one of the following conditions exist, a failure of the coolant temperature sensor may have occurred:
Sensor output is open.
Sensor output is shorted to ground or supply.
Measured reading of the coolant temperature is out of specification.The ECM will detect the failure of the coolant temperature sensor. The diagnostic lamp will warn the operator about the status of the coolant temperature sensor. The coolant temperature related strategies will be disabled. The failure of the coolant temperature sensor will not cause a shutdown of the engine or any horsepower change.Engine Oil Pressure Sensor
The engine oil pressure sensor (1) can detect engine oil pressure for diagnostic purposes. The engine oil pressure sensor sends a signal to the Electronic Control Module (ECM).Low Oil Pressure Warning
The setpoint is dependent upon the engine rpm. The fault will be active and logged only if the engine has been running for more than 15 seconds. Very Low Oil Pressure Warning
The very low oil pressure setpoint is dependent upon the engine rpm. If the customer specified parameter is selected, the ECM will derate the engine power. The engine horsepower will be limited.Failure of the Engine Oil Pressure Sensor
If one of the following conditions exist, a failure of the engine oil pressure sensor may have occurred:
The engine oil pressure sensor is open.
The engine oil pressure sensor is shorted to ground or supply.
Measured reading of the oil pressure is out of specification.The ECM will detect the failure of the engine oil pressure sensor. The diagnostic lamp warns the user about the status of the engine oil pressure sensor. The oil pressure related strategies will be disabled. The failure of the engine oil pressure sensor will not cause a shutdown of the engine or any horsepower change.Engine Speed/Timing Sensor
If the ECM does not receive a signal from engine speed/timing sensor (6) and (7), the "DIAGNOSTIC" lamp will indicate a diagnostic fault code which will be logged in the ECM memory.Intermittent failure of the sensor will cause erratic engine control.Fuel Pressure Sensor
Fuel pressure sensor (8) monitors the fuel filter outlet pressure. Low fuel pressure or high fuel pressure will not cause a shutdown of the engine or any horsepower change. Fuel pressure that is outside of the normal range will affect the engine performance. If the fuel filter outlet pressure is low, the fuel filter may need to be replaced.
Table 2
Fuel Pressure Sensor
Minimum allowable pressure of the fuel transfer pump at full load speed 415 kPa (60 psi)
Minimum allowable pressure in