RISER AS 4780940 - Caterpillar

Illustration 1 g06149503
Connections of the Lift Cylinder Pressure Sensor
This diagnostic code is associated with the Lift Cylinder Rod Pressure Sensor. CID 458 FMI 08 means that the Machine Electronic Control Module (ECM) has determined that:
The signal frequency is not within the expected range
The signal pulse width is not within the expected rangeThe output frequency of the position sensor is approximately 500 Hz. The duty cycle of the signal changes as the position sensor moves.The possible causes of this diagnostic code are listed below:
The wrong sensor has been installed
The sensor has failed
Intermittent connections or poor connections
Mechanical devices are loose
The ECM has failed. The ECM is unlikely to failNote: The following test procedure may create other diagnostic codes. Ignore these created diagnostic codes and clear the diagnostic codes when the original diagnostic code has been corrected.Ensure that the diagnostic code of CID 458 FMI 08 is active before performing this procedure.Note: Use the 146-4080 Digital Multimeter for the measurements in this procedure.System Response:The kickouts will not function properly. The implements will function slowly.Test Step 1. Check For Power At The Sensor
Do not disconnect the harness connector from the sensor.
Turn the key start switch and the disconnect switch to the ON position. Do not start the engine.
At the sensor harness connector for the implement control levers, insert 7X-1710 Multimeter Probes along the contacts of the system power supply 1 (wire P769-YL(Yellow)) and along ground contact 2 (wire P770-WH(White)).
Measure the voltage of the system power supply.
With a multimeter probe still connected to system power, measure the voltage at a known good frame ground.Expected Result:Both voltage measurements are approximately 8V 1.0 VDC.Results:
YES - Both voltage measurements are approximately +8V 1.0 VDC. The power supply for the sensor is correct. Proceed to Test Step 3.
NO - If both voltage measurements are less than +8V 1.0 VDC, the power supply circuit is not correct.Repair: An interruption of the power circuit will cause multiple diagnostic codes to activate for sensors that are powered from the circuit.Check the harness for opens or for poor connections in the power circuit.Refer to the complete Electrical System Schematic of the machine. Examine all of the connectors that are in the circuits. Ensure that the connections are clean, that all connections are secure and that all connections are in good condition.Repair or replace the faulty power supply circuit.STOPTest Step 2. Check The Signal Circuit Of The Sensor
Turn the key start switch and the disconnect switch to the OFF position.
Remove the 7X-1710 Multimeter Probe from wire P769-YL(Yellow)and insert the probe along the signal wire E416-PU(Purple).
Insert the 7X-1710 Multimeter Probe along the ground wire P770-WH(White).
Turn the disconnect switch and the key start switch to the ON position. Do not start the engine.
Monitor the signal of the sensor with the 146-4080 Digital Multimeter.
Without disconnecting the sensor, take the sensor through the full operating range of the sensor.Note: To take the sensor through the full operating range of the sensor, some machines may require the engine started.Expected Result:The sensor signal responds