SWITCH AS-PRESSURE 5W9972 - Caterpillar

Illustration 1 g01427880
Schematic for the Counterbalance DialThis diagnostic code is associated with the Counterbalance Dial. The FMI 04 means that the ECM has determined that the voltage of the circuit for the dial is below normal. Note: The Implement (Screed) ECM is located under the Screed Platform.The possible causes of this diagnostic code are listed below:
The signal circuit for the dial is shorted to ground.
The dial has failed.
The ECM has failed. This is unlikely. Note: 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 2577 FMI 04 is active before performing this procedure. Note: Use the 146-4080 Digital Multimeter for the measurements in this procedure.System Response:When this diagnostic code is active, the following occurs:
Counter balance screed assist mode will maintain pre-fault setting until propel lever returns to neutral.
After propel lever returns to neutral, screed assist mode will operate at 50% setting.
Operator station fault lamp is active.Test Step 1. CHECK THE DIAL
Turn the disconnect switch and the key start switch to the ON position.
Ensure that the diagnostic code is active.
Observe the status of the diagnostic code. Disconnect the dial from the machine harness.Expected Result:The CID 2577 FMI 04 remains active. The FMI has not changed and the "04" is still active.Results:
OK - The diagnostic code remains active. The dial is correct. Proceed to Test Step 2.
NOT OK - The diagnostic code is no longer active. The dial has failed.Repair: Replace the dial.STOPTest Step 2. CHECK THE WIRING HARNESS OF THE DIAL FOR A SHORT TO GROUND.
Turn the key start switch and the disconnect switch to the OFF position.
Disconnect the machine harness from the dial.
Disconnect the machine harness connector from the ECM.
At the machine harness connector for the ECM, measure the resistance from the signal contact J1-37 (wire C862-GN) of the machine harness to all possible sources of ground. Measure the resistance to all contacts of the machine harness connectors for the ECM.Expected Result:Each resistance measurement is greater than 5000 ohms.Results:
OK - Each resistance measurement is greater than 5000 ohms. The machine harness is correct. Proceed to Test Step 3.
NOT OK - One or more resistance measurements is not correct. There is a short in the machine harness. Repair: The short is between signal contact J1-37 (wire C862-GN) and the circuit with the low resistance measurement. Repair the machine harness or replace the machine harness.STOPTest Step 3. CHECK THE DIAL
Attach a 6V-7070 Digital Multimeter with 7X-1710 Multimeter Probes to the receptacle of the dial without disconnecting the connectors. Connect the ground lead to pin "B" and connect the signal lead to connector pin "C".
Turn the disconnect switch and the engine start switch to the ON position, but do NOT start the engine.
Operate the dial.Expected Result:The resistance should be 0 ohms at the minimum setting of the dial. As the dial is rotated clockwise, the resistance will increase to 950 10 ohms at the maximum setting.Results:
OK