SHAFT 7S4626 - Caterpillar

Illustration 1 g00956592
This diagnostic code is associated with the left conveyor speed dial (right station). The FMI 08 means that the ECM has determined that the signal frequency or the signal pulse width is not within the expected range.The output frequency of the sensor is approximately 5000 Hz. The duty cycle of the signal varies as the position sensor moves. The duty cycle varies from 2% to 98%. The possible causes of this diagnostic code are listed below:
The sensor has failed.
Intermittent connections or poor connections
Mechanical devices are loose.
The ECM has failed. ECM failure 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 1769 FMI 08 is active before performing this procedure.Note: Use the 146-4080 Digital Multimeter for the measurements in this procedure. System Response:When the diagnostic code is active, the following response occurs:
The machine ECM maintains the pre-fault value until neutral reset occurs.
The sensor defaults to 50% after the neutral reset has taken place.
The fault lamp for the material system, the tamp system, and the auxiliary system is ON.
The action lamp is ON.Test Step 1. CHECK FOR POWER AT THE SENSOR.
Do not disconnect the harness connector from the sensor.
At the back of the harness connector for the sensor, insert a 7X-1710 Multimeter Probe along the voltage supply wire (contact A).
Turn the key start switch and the disconnect switch to the ON position.
Measure the voltage from contact A to frame ground.Expected Result:The voltage is 8.0 0.5 DCV.Results:
OK - The voltage is 8.0 0.5 DCV. Proceed to Test Step 3.
NOT OK - The voltage is not 8.0 0.5 DCV. Proceed to Test Step 2.Test Step 2. CHECK THE RELAY
Turn the key start switch and the disconnect switch to the OFF position.
Remove relay 1 (operating station) and insert a jumper from contact 30 to contact 87a at the relay.
Turn the key start switch and the disconnect switch to the ON position.
At the back of the harness connector for the sensor, insert a 7X-1710 Multimeter Probe along the voltage supply wire (contact A).
Measure the voltage from contact A to frame ground.Expected Result:The voltage is 8.0 0.5 DCV.Results:
OK - The voltage is 8.0 0.5 DCV. The relay 1 (operator station) has failed.Repair: Replace the relay and verify that the new relay corrects the problemSTOP
NOT OK - The voltage is not 8.0 0.5 DCV. The voltage supply wire in the machine harness has failed.Repair: Repair the machine harness or replace the machine harnessSTOPTest Step 3. CHECK THE SIGNAL CIRCUIT OF THE SENSOR.
Turn the key start switch and the disconnect switch to the OFF position.
At the back of the harness connector, remove the 7X-1710 Multimeter Probe from contact A and insert the probe along the signal wire (contact C).
At the back of the harness connector for the sensor, insert the 7X-1710 Multimeter Probe along the ground wire (contact B).
Turn the disconnect switch