PISTON 2782246 - Caterpillar

Illustration 1 g02102854
Connections of auxiliary lever 1 position sensorThis diagnostic code is associated with the auxiliary lever 1 position sensor. The position sensor is located in the attachment for the auxiliary control pod. The FMI 08 is activated when the Implement ECM 2 detects a signal frequency or a signal pulse width from the sensor that is not within the expected range.The Implement ECM 2 communicates this condition to the Implement ECM over the SAE J1939 Data Link and the Implement ECM will activate this diagnostic code.The position sensor is a PWM sensor that operates at a frequency of approximately 500 100 Hz. The position sensor sends a PWM input signal to the Implement ECM 2. The variations in the duty cycle of the signal follow:
When the lever is at the full upward position, the duty cycle will be approximately 10%.
When the lever is at the full downward position, the duty cycle will be approximately 90%.
When the lever is in the center position, the duty cycle will be approximately 50%. The possible causes of this diagnostic code are listed below:
The sensor has failed or a mechanical connection has failed.
Intermittent connections or poor connections
The ECM has failed. This is unlikely.Before performing this procedure, inspect the harness connectors that are involved in the circuit. Poor connections can often be the cause of a problem in an electrical circuit. Inspect the connections for the following:
Connections are clean.
Connections are secure.
Connections are in good condition. If a problem with a connection is found, correct the problem and verify that this diagnostic code is active before performing this procedure.Note: The following test procedure may create other diagnostic codes. Ignore these created diagnostic codes and clear the diagnostic codes when the problem has been corrected.Test Step 1. CHECK THE DUTY CYCLE AND THE SIGNAL FREQUENCY AT THE SENSOR
Turn the key start switch and the disconnect switch to the OFF position.
At the machine harness connector J1 for the auxiliary control pod, use a 151-6320 Removal Tool to remove the signal wire U706-BR and the socket at contact J1-2 from the harness connector. The machine harness connector J1 remains connected to the auxiliary control pod.
Turn the disconnect switch and the key start switch to the ON position.
At the connector J1 for the auxiliary control pod, insert a 7X-1710 Multimeter Probe along the return contact J1-3 (wire A296-BK).
Use the other multimeter probe to make contact through the harness connector with the pin 2 for the position sensor on the connector of the control pod.
With the auxiliary lever in the stationary condition, measure the frequency of the signal from the sensor.
Measure the duty cycle of the sensor signal between the connector contacts J1-2 and J1-3 for the auxiliary control pod. Slowly move the lever to the full upward position and observe the duty cycle of the sensor signal. Slowly move the lever to the full downward position while the duty cycle of the sensor signal is observed.Expected Result:The signal frequency of the position sensor for the auxiliary lever 1