SPACER 2120137 - Caterpillar

Illustration 1 g02598216
Schematic of the "Stick Angle" Sensor This diagnostic code is associated with the "Stick Angle" Sensor. The FMI 08 diagnostic code means that the ECM has determined that the signal frequency is not within the expected range.The "Stick Angle" Sensor has an output frequency of approximately 500 Hz. The duty cycle of the signal changes as the position of the boom is changed. The duty cycle varies from approximately 19% at the minimum position to approximately 77% at the maximum position. The duty cycle is approximately 48% at the center position.The possible causes of this diagnostic code are listed below:
The "Stick Angle" Sensor has failed.
Intermittent connections or poor connections
The ECM has failed. A failure of the Machine ECM 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 2426 FMI 08 is active before performing this procedure.Note: Use the 146-4080 Digital Multimeter or the equivalent for the measurements in this procedure. Test Step 1. CHECK FOR POWER AT THE "STICK ANGLE" SENSOR.
Do not disconnect the harness connector from the joystick.
Turn the key start switch and the disconnect switch to the ON position.
At the back of the harness connector for the joystick, insert a 7X-1710 Multimeter Probe along the voltage supply wire 159-BU.
Measure the voltage from the voltage supply wire (159-BU) to frame ground.Expected Result:The voltage is approximately 24 VDC.Results:
OK - The voltage is approximately 24 VDC. Proceed to Test Step 2.
NOT OK - The voltage is not approximately 24 VDC. The circuit is open. Repair: Repair the machine harness or replace the machine harness.STOPTest Step 2. CHECK THE SIGNAL CIRCUIT OF THE "BOOM ANGLE" SENSOR FOR THE CORRECT DUTY CYCLE.
Turn the key start switch and the disconnect switch to the OFF position.
At the back of the harness connector for the sensor, remove the 7X-1710 Multimeter Probe from the supply wire (159-BU) and insert the probe along the signal wire J851-BR.
At the back of the harness connector for the sensor, insert a 7X-1710 Multimeter Probe along the ground wire 235-BK .
Turn the disconnect switch and the key start switch to the ON position.
Monitor the duty cycle of the "Stick Angle" Sensor with the 146-4080 Digital Multimeter .
Without disconnecting the angle sensor or the hardware associated with the angle sensor from the machine, move the joystick through the entire range of motion.Note: On some machines, starting the engine may be necessary to move the joystick control through the entire range of motion.Expected Result:The duty cycle value of the sensor responds in the manner that is described at the beginning of this procedure.Results:
OK - The duty cycle value of the sensor responds correctly. The "Stick Angle" Sensor is operating correctly. Proceed to Test Step 3.
NOT OK - The duty cycle value of the sensor does not respond correctly. The "Stick Angle" Sensor is not operating correctly.Repair: Replace the entire sensor.STOPTest Step 3. CHECK THE