ELBOW GP-EXHAUST 4314763 - Caterpillar

Illustration 1 g02151326
Connections of the 3 Function Auxiliary Control
This diagnostic code is associated with the 3 Function Auxiliary Thumbroller Control (Auxiliary Lever #3 Position Sensor). The FMI 03 diagnostic code means the input signal from the control and the signal voltage is above the acceptable range.The signal receives power from the battery. The control sends a PWM input signal to the Implement ECM. The duty cycle of the signal varies from approximately 20 percent at the full forward position to approximately 80 percent at the full left position. When the thumbroller is at the center position, the duty cycle will be approximately 50 percent. The control is a PWM control that operates at a frequency of approximately 500 80 Hz.The possible causes of this diagnostic code are listed:
The power supply circuit is open.
The fuse has blown.
The return circuit is open.
The signal circuit is open.
The signal circuit is shorted to another voltage source.
The control has failed.
The ECM has failed. An ECM failure is unlikely. Test Step 1. Check the power supply circuit to the control
Turn the disconnect switch and the key start switch to the ON position. Do not start the engine.
At the machine harness connector for the control, insert a multimeter probe along contact "1" wire (176-OR(Orange)) and along contact "2" wire (200-BK(Black)). Do not disconnect the machine harness connector from the control.
Measure the voltage. Expected Result:The voltage measurement is between 23.5 VDC and 24.5 VDC.Results:
YES - The voltage measurement is between 23.5 VDC and 24.5 VDC. The power circuits for the control are correct. Proceed to Test Step 2.
NO - The voltage measurement is less than 23.5 VDC. The power supply for the control is not correct.Repair: There is an open circuit or a bad connection in the machine harness. Verify that the fuse is in good condition and is not blown. Wire (176-OR(Orange)) may have an open circuit. Refer to Electrical System Schematic, KENR8916. Examine all of the