PROPELLER AS 3918540 - Caterpillar

Illustration 1 g02141178
Connections of the direction/speed control lever
The diagnostic code is associated with signal 2 for the forward/neutral/reverse switch.The forward/neutral/reverse switch is a three-position rocker switch that is located on the direction/speed control lever. The switch contains two hall effect sensors that provide PWM signals to the ECM in order to indicate the position of the rocker switch.The FMI 08 diagnostic code is activated when the ECM reads the input signal outside the expected range.The conditions that can cause this diagnostic code are listed:
The sensor has failed.
Intermittent connections or poor connections exist in the sensor circuit.
The ECM has failed. An ECM failure is unlikely. The ECM monitors the two signals in order to determine the status of the three-position switch. Each of the hall effect sensors in the switch sends a PWM signal to the ECM. The ECM expects the duty cycle of both of the sensors to be similar. The acceptable duty cycle range for each switch position is illustrated in Table 1.
Table 1
Signal for Switch Positions
Position Percentage of the duty cycle for sensor 1 at J2-48 wire (A887-BU(Blue)) Percentage of the duty cycle for sensor 2 at J2-49 wire (A889-GY(Grey))
Forward 85 5 85 5
Neutral 50 10 50 10
Reverse 13 7 13 7 The sensor 1 receives 10 VDC power and ground from the ECM. The sensor 2 receives 8 VDC power and ground from the ECM.Note: Check for an active CID 0041 - FMI 03 diagnostic code. A problem with the 10 VDC supply can cause this diagnostic code to be active. Perform the CID 0041 - FMI 03 troubleshooting procedure and clear the diagnostic code before performing this procedure.System Response:If only one of the circuits has an active diagnostic code, then the ECM allows normal machine operation to continue. If a diagnostic code is active for both of the input circuits, the ECM shifts the transmission to neutral. The operation of the machine is interrupted because the ECM is unable to determine the status of the switch. The forced shift to neutral indicates that both of the input circuits are not operating correctly. A CID 3527 is activated when the ECM reads both of the input signals and the signals are outside the acceptable range.Note: The following test procedure may create other diagnostic codes. Ignore these created diagnostic codes and clear these diagnostic codes when the original diagnostic code has been corrected. Ensure that the diagnostic code of CID 2994 - FMI 08 is active before performing this procedure.Note: Use a digital multimeter for the measurements in this procedure.Test Step 1. Check the switch operation
Turn the disconnect switch and the key start switch to the OFF position.
At the 12-pin connector for the control lever, use a wire removal tool in order to remove contact "8" wire (A889-GY(Grey)) from the harness connector. The harness connector remains connected to the control lever.
At the 12-pin connector, insert the negative multimeter probe along contact "12" wire (J766-PU(Purple)). Insert the positive multimeter probe along contact