PIPE 0544048 - Caterpillar

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Troubleshooting Chart
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Schematic for the Position Sensor (Lift Linkage)This diagnostic code is recorded when the ECM for the payload system determines that the signal from the lift position sensor is incorrect.The possible causes of this diagnostic code are listed:
The signal circuit is open.
The +battery circuit from the electrical system to the sensor is open.
The signal circuit is shorted to the battery voltage.
The signal circuit is shorted to ground.
The rotary position sensor for the lift linkage has been rotated past the allowable range.
The sensor is not adjusted properly.Test Step 1. CHECK THE VOLTAGE FROM THE SIGNAL CIRCUIT
Turn the disconnect switch and the key start switch to the OFF position.
Disconnect the machine harness from the ECM.
Disconnect the sensor linkage from the bail.
Turn the disconnect switch and the key start switch to the ON position.
Ensure that the diagnostic code is still active.
At the connector for the ECM, measure the voltage between contact 20 (wire C530-BU) and contact 21 (wire 251-BK).Note: Measure the voltage while the lever that is connected to the position sensor is moved up and down.Note: Do not extend the position sensor beyond the maximum limits. Damage to the sensor may occur.Expected Result:The voltage changes evenly from .5 DCV to 5.5 DCV.Results:
YES - The voltage changes evenly from low voltage to high voltage. The voltage will vary from .5 DCV to 5.5 DCV. On some machines, the voltage will vary from .5 DCV to 10 2 DCV. The voltage is correct. Proceed to Test Step 5.
NO - The voltage remains constant or the voltage changes erratically. The voltage does not change evenly between .5 DCV and 5.5 DCV. The voltage is not correct. Proceed to Test Step 2.Test Step 2. CHECK THE +BATTERY VOLTAGE
Turn the disconnect switch and the key start switch to the OFF position.
Disconnect the connector for the lift position sensor.
Turn the disconnect switch and the key start switch to the ON position.
At the connector for the position sensor, measure the voltage between contact A (wire 146-GY) and contact B (wire 299-BK).Expected Result:The voltage is between 18 DCV and 24 DCV.Results:
YES - The voltage is between 18 DCV and 24 DCV. The + battery voltage is correct. Proceed to Test Step 3.
NO - The voltage is less than 18 DCV. There may be an open or a short in