992K Wheel Loader Electrohydraulic System MID 082 - CID 2416 - FMI 08 Caterpillar

Conditions Which Generate This Code:

Illustration 1	g01965333
Schematic for the Right Implement Pump Pressure Sensor

This diagnostic code is associated with the Right Implement Pump Pressure Sensor. The FMI 08 means that the ECM has determined that the signal of the sensor has an abnormal frequency or the signal pulse width is not within the expected range.

The output frequency of the pressure sensor is approximately 500 hertz. The duty cycle of the signal changes as the pressure changes.

The signal may have one of the following characteristics:

• Abnormal frequency

• Abnormal pulse width

• Abnormal period

The possible causes of this condition are listed below:

• The signal circuit is shorted to the +battery circuit or shorted to ground intermittently.

• The signal circuit is open intermittently or the sensor is disconnected.

• The sensor may have failed.

• The ECM may have failed. This is unlikely.

Note: This diagnostic code is usually caused by an intermittent condition. The diagnostic code is active and the diagnostic code is inactive over a period of time.

Note: Ensure that there are no active CID 262 diagnostic codes for the 5 volt sensor power supply before performing this procedure. Ensure that CID 2416 FMI 08 diagnostic code is active. This test procedure may cause other diagnostic codes. Clear these diagnostic codes when the original diagnostic code has been corrected.

Test Step 1. CHECK FOR POWER AT THE SENSOR

1. Disconnect the harness connector from the sensor.

2. Turn the key start switch and the disconnect switch to the ON position.

3. At the harness connector for the sensor, measure the voltage between contact "A" (wire 146-GY(Grey)) and contact "B" (wire 299-BK(Black)).

Expected Result:

The voltage is between 8 VDC and 32 VDC.

Results:

• OK - The voltage measurement is between 8 VDC and 32 VDC. Proceed to Test Step 3.

• NOT OK - The voltage measurement is not between 8 VDC and 32 VDC. There is a problem in the supply circuit. Proceed to Test Step 2.

Test Step 2. CHECK THE POWER SUPPLY AT THE ECM

The machine harness connectors "J1" and "J2" are connected to the ECM for this step.

1. Turn the key start switch to the ON position.

2. At the machine harness connector of the ECM, insert the 7X-1710 Multimeter Probe into the back of the connectors at contacts "J2-49" (wire R788-BU(Blue)) and "J1-70" (wire 299-BK(Black)). Measure the voltage.

Expected Result:

The voltage measurement is between 8 VDC and 32 VDC.

Results:

• OK - The voltage measurement is between 8 VDC and 32 VDC. The ECM power supply is correct.

  Repair: There is a problem in the sensor circuit in the machine harness. Either the supply wire R788-BU(Blue) or the return wire 299-BK(Black) has a bad connection or an open in the machine harness. Refer to the complete machine Electrical Schematic. Check the resistance of each circuit from the ECM connection to the sensor connection in order to determine the circuit that is open. Then, check each wire from connection point to connection point for an open. Repair the machine harness or replace the machine harness.

  STOP

• NOT OK - The voltage measurement is not between 8 VDC and 32 VDC. The ECM may have failed.

  Repair: Perform this procedure again. If the correct voltage is not found at the contact of the power supply with the key start switch in the ON position, the ECM may have failed.

  It is unlikely that the ECM has failed. Exit this procedure and perform this procedure again. Contact your dealership's Technical Communicator for possible consultation with AVSpare. This consultation may greatly reduce repair time. If the ECM must be replaced, refer to the Testing and Adjusting, "Electronic Control Module (ECM) - Replace" Section of this manual.

  STOP

Test Step 3. CHECK THE SIGNAL CIRCUIT FOR A SHORT IN THE HARNESS

1. Turn the key start switch and the disconnect switch to the OFF position. The sensor remains disconnected from the machine harness.

2. Disconnect the machine harness connectors "J1" and "J2" from the ECM.

3. Measure the resistance between contact "J2-49" (wire R788-BU(Blue)) and all contacts that are used in the machine harness connectors for the ECM.

Expected Result:

The resistance of each measurement 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 - One or more of the resistance measurements is less than 5 ohms. The signal circuit is shorted to another circuit in the harness.

  Repair: There is a short in the machine harness between wire R788-BU(Blue) and the circuit with the low resistance measurement. Repair the machine harness or replace the machine harness.

  STOP

Test Step 4. CHECK THE SIGNAL CIRCUIT FOR AN OPEN IN THE HARNESS

1. The key start switch and the disconnect switch remain in the OFF position.

2. The harness connectors remain disconnected from the sensor and the ECM.

3. At the machine harness connector for the sensor, place a jumper wire between contact "B" (wire 299-BK(Black)) and contact "C" (wire R788-BU(Blue)).

4. At the harness connectors for the ECM, measure the resistance between contact "J2-49" (wire R788-BU(Blue)) and contact "J1-70" (wire 299-BK(Black)).

Expected Result:

The resistance measurement is less than 5 ohms.

Results:

• OK - The resistance measurement is less than 5 ohms. The circuit is correct. Proceed to Test Step 5.

• NOT OK - The resistance measurement is greater than 5 ohms. The signal circuit is in the open connection or in the bad connection in the harness.

  Repair: There is an open or a bad connection in wire R788-BU(Blue) in the machine harness. Refer to the complete machine Electrical Schematic. Verify the following:

  • All connections are clean.

  • All connections are secure.

  • All connections are in good condition.
  Check the continuity of wire R788-BU(Blue) from each connection point to the next connection point. Repair the machine harness or replace the machine harness.

  STOP

Test Step 5. CHECK THE STATUS OF THE DIAGNOSTIC CODE

1. Inspect the harness connectors and clean the contacts of the machine harness connectors.

2. Reconnect all harness connectors.

3. Turn the disconnect switch and the key start switch to the ON position.

4. Operate the machine.

5. Check the status of the CID 2416 FMI 08 diagnostic code.

Expected Result:

The CID 2416 FMI 08 diagnostic code is not active.

Results:

• OK - The CID 2416 FMI 08 diagnostic code is not active. The diagnostic code does not exist at this time. The initial diagnostic code was probably caused by a poor connection or a short at one of the connectors that was disconnected and reconnected. Resume normal operation.

  STOP

• NOT OK - The CID 2416 FMI 08 diagnostic code is active. The diagnostic code has not been corrected. The sensor may be faulty.

  Repair: Check the machine harness again. Use the AVSpare Electronic Technician (Cat ET) service tool in order to perform a wiggle test on the machine wiring harness. The Wiggle Test can detect the following in the machine wiring harness.

  • Momentary shorts

  • Intermittent shorts

  • Opens
  If a problem with the machine harness is not found, replace the sensor. After the sensor is replaced, perform this test step again in order to ensure that the sensor is operating correctly. After replacing the sensor, if the diagnostic code is still active, the ECM is faulty.

  It is unlikely that the ECM has failed. Exit this procedure and perform this procedure again. Contact your dealership's Technical Communicator for possible consultation with AVSpare. This consultation may greatly reduce repair time. If the ECM must be replaced, refer to the Testing and Adjusting, "Electronic Control Module (ECM) - Replace" Section of this manual.

  STOP