ROD 0505665 - Caterpillar

Illustration 1 g02404766
Connections of the Lift Lever Position Sensor
This diagnostic code is recorded when the Implement ECM reads the Lift Lever Position Sensor and the voltage of the signal is below normal. The position sensor is located in the lift lever assembly.Each lever position sensor is supplied system voltage through the right column, fuse F39 in the switched upper fuse panel (10A 146-GY(Grey)). Each sensor is supplied an ECM ground circuit (C214-BK(Black)) connection from the Implement ECM J1-70 contact and the Machine ECM J1-70 contact.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 ECM. The duty cycle of the signal will vary from 10% to 90%. The variations in the duty cycle of the signal follow:
Table 1
Lever Position Acceptable Sensor PWM Duty Cycle (Percent)
Full Forward 7 to 14
Centered 50 4
Full Rearward 85 to 93 The possible conditions that could cause this diagnostic code are:
The linkage is loose or damaged.
The signal circuit is shorted to a ground.
The sensor has failed.
The ECM has failed. This condition is unlikely. Note: 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. Verify that all connections in the circuit are clean, that all connections are secure and that all 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 SENSOR
Turn the disconnect switch and the key start switch to the ON position.
Disconnect the machine harness connector C2 from the implement control lever assembly. Observe the status of the active CID 0352 FMI 04 diagnostic code. Expected Result:The status of the CID 0352 FMI 04 diagnostic code did not change when the connector for the lever assembly was disconnected. A CID 0352 FMI 03 diagnostic code has not been activated by the ECM. The CID 0352 FMI 04 diagnostic code remains active when the connector for the lever assembly is disconnected.Results:
OK - The CID 0352 FMI 04 diagnostic code remains active when the connector for the lever assembly is disconnected. The sensor is not the cause of the problem. Proceed to Test Step 2.
NOT OK - The CID 0352 FMI 04 diagnostic code is no longer active when the connector for the lever assembly is disconnected. A CID 0352 FMI 03 diagnostic code is activated by the ECM when the connector for the lever assembly is disconnected. The machine harness and the ECM are operating correctly.Repair: The operation of the sensor is the cause of the problem. Replace the lever assembly. After replacement, verify that the operation is correct before operating the machine.STOPTest Step 2. CHECK THE SIGNAL CIRCUIT