CAMSHAFT 1878646 - Caterpillar

Illustration 1 g02050533
Connections of the engine speed sensorThis diagnostic code is associated with the engine speed sensor. 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 possible causes of this diagnostic code are listed below:
The sensor has failed.
The spacing of the sensor is incorrect.
Intermittent connections or poor connections
Mechanical devices are loose.
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 0190 FMI 08 is active before performing this procedure.Note: Use a digital multimeter for the measurements in this procedure. Test Step 1. 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 for the sensor, insert a multimeter probe along contact 2 (wire L912-WH) for the signal wire.
At the back of the harness connector for the sensor, insert a multimeter probe along contact 1 (wire L913-OR) for the ground wire.
Turn the disconnect switch and the key start switch to the ON position.
Start the engine.
Monitor the signal of the sensor with a digital multimeter.Expected Result:The sensor's signal responds in the manner that is described at the beginning of this procedure.Results:
OK - The sensor's signal responds correctly. The sensor is operating correctly. Proceed to Test Step 2.
NOT OK - The sensor's signal does not respond correctly. The sensor is not operating correctly.Repair: Check the sensor for proper installation and distance from the gear teeth. See Testing and Adjusting, "Speed Sensor - Adjust" for more information. Perform this procedure again. If the diagnostic code is still active, replace the sensor.STOPTest Step 2. CHECK THE SIGNAL CIRCUIT AT THE ECM.
Turn the key start switch and the disconnect switch to the OFF position.
Insert the multimeter probes into the back of the ECM connector along J1-2 (wire L912-WH) and J1-3 (wire L913-OR).
Turn the disconnect switch and the key start switch to the ON position.
Start the engine.
Monitor the signal of the sensor with a digital multimeter.Expected Result:The sensor's signal responds in the manner that is described at the beginning of this procedure.Results:
OK - The sensor's signal responds correctly. The sensor is operating correctly. Proceed to Test Step 3.
NOT OK - The sensor's signal does not respond correctly. The harness has failed. Repair: Repair the machine harness or replace the machine harness.STOPTest Step 3. CHECK THE SIGNAL CIRCUIT FOR A SHORT IN THE HARNESS.
The key start switch and the disconnect switch remain in the OFF position.
Disconnect the machine harness connectors from the sensor and the ECM.
Measure the resistance between contact J1-2 (wire L912-WH) and all contacts that are used in the machine harness connectors for the ECM.Expected Result:The resistance is greater than 5000 ohms.Results:
OK - The resistance is greater than 5000 ohms. The circuit is correct. Proceed to Test Step 4.
NOT OK - The resistance