Cat® Command For Hauling Caterpillar

MID 039 - CID 0838 - FMI 03

Usage:

- AT6

Conditions Which Generate This Code:

MID 039 - Machine Control Module

CID 0838 - Left Front Strut Pressure Sensor

FMI 03 - Voltage Above Normal

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Illustration 1	g06042376
Mini schematic of the left front strut pressure sensor circuit

This diagnostic code appears when the Input/Output Module (I/O Module) has determined the Left Front Strut Pressure sensor voltage is above normal.

The output frequency of the sensor changes as the pressure in the suspension cylinder changes. The sensor is powered by the machine electrical system.

Test Step 1. CHECK THE CONTROL MODULES FOR PROPER SOFTWARE

Note: Use the release-specific software summary for the compatible software version

Check the software version of the Machine Control Module (MCM).
Check the software version of the VIMS Application Module.
Check the software version of I/O Module.

Expected Result:

The proper version of software is installed.

Results:

OK - The software version is correct on the MCM, the VIMSApplication Module and the I/O Module. Proceed to Test Step 2.
NOT OK - The software version is incorrect on the MCM, the VIMSApplication Module or the I/O Module.
Repair: Flash the proper software to the ECM. Refer to Special Instruction, REHS3692, "Procedure to Flash an Electronic Control Module". Cycle the keyswitch in order to initialize new software. Ensure that the diagnostic code is no longer active.

STOP

Test Step 2. CHECK THE SENSOR SUPPLY VOLTAGE

The keyswitch and battery disconnect switch remain in the ON position.
Locate the suspect sensor.
Identify the sensor wires and connector contacts. Do not disconnect any harness connectors.
At the sensor connector, insert 7X-1710 Multimeter Probe leads beside contact A (wire 113-OR(Orange)) and contact B (wire J849-WH(White)).
Measure the voltage.

Expected Result:

The voltage is between 22.0 VDC and 29.5 VDC.

Results:

OK - The voltage is between 22.0 VDC and 29.5 VDC. Proceed to Test Step 3.
NOT OK - The voltage is not between 22.0 VDC and 29.5 VDC.
Repair: Trace the +V and Ground circuits in the harness. Repair the machine harness or replace the machine harness

STOP

Test Step 3. CHECK SENSOR SIGNAL VOLTAGE

The keyswitch and battery disconnect switch remain in the ON position.
At the sensor connector, insert 7X-1710 Multimeter Probe leads beside contact C (wire 859-YL(Yellow)) and contact B (wire J849-WH(White)).
Measure the voltage.

Expected Result:

The voltage is between 1.0 VDC and 9.0 VDC.

Results:

OK - The voltage is between 1.0 VDC and 9.0 VDC. Proceed to Test Step 8.
NOT OK - The voltage is less than 1.0VDC or greater than 9.0 VDC. Proceed to Test Step 4.

Test Step 4. CHECK THE SIGNAL CIRCUIT VOLTAGE

The keyswitch and battery disconnect switch remain in the ON position.
Disconnect the sensor from the harness.
At the harness connector for the sensor, measure the voltage between contact C (wire 859-YL(Yellow)) and contact B (wire J849-WH(White)).

Expected Result:

The voltage is less between 1.0VDC and 9.0 VDC.

Results:

NOT OK - The voltage is less than 1.0VDC or greater than 9.0 VDC. Proceed to Test Step 5.
OK - The voltage is between 1.0 VDC and 9.0 VDC. The voltage is correct, the sensor has failed.
Repair: Replace the sensor.

STOP

Test Step 5. CHECK THE SIGNAL VOLTAGE AT THE VIMS APPLICATION MODULE

Turn the keyswitch and battery disconnect switch to the OFF position.
Disconnect the J1 and J2 machine harness connectors from the Input/Output Module (I/O Module).
Turn the keyswitch and battery disconnect to the ON position.
At the VIMS Application Module, insert 7X-1710 Multimeter Probe leads beside contact 46 (Wire 859-YL(Yellow)) and contact 69 (Wire J849-WH(White)).
Measure the voltage.

Expected Result:

The voltage is between 1.0 VDC and 9.0 VDC.

Results:

YES - The voltage is between 1.0 VDC and 9.0VDC. Proceed to Test Step 7.
NO - The voltage is less than 1.0 VDC. Proceed to Test Step 6.
NO - The voltage is greater than 9.0 VDC.
Repair: Repeat this procedure. If the problem remains, replace the sensor. After the sensor is replaced, repeat this Test Step again. If the diagnostic code is still active, the VIMS Application Module may be faulty. However, VIMS Application Module failure is unlikely. Exit this procedure and perform this procedure again. If the cause of the diagnostic code is not found, replace the ECM. Refer to Testing and Adjusting, KENR8394, "Electronic Control Module (ECM) – Replace".

STOP

Test Step 6. CHECK THE HARNESS FOR A SHORT TO GROUND

Turn the keyswitch and battery disconnect switch to the OFF position.
Disconnect the machine harness connector form the VIMS Application Module.
At the machine harness connector ME-C2, measure the resistance between connector ME-C2-46 (Wire 859-YL(Yellow)) and all ME-C2 contacts that are connected to ground or to frame ground.

Expected Result:

The resistance measurement is greater than 5000 ohms.

Results:

YES - The resistance is greater than 5000 ohms. The harness does not have a short to ground.
Repair: Repeat this procedure. If the problem remains, replace the sensor. After the sensor is replaced, repeat this Test Step again. If the diagnostic code is still active, the VIMS Application Module may be faulty. However, VIMS Application Module failure is unlikely. Exit this procedure and perform this procedure again. If the cause of the diagnostic code is not found, replace the ECM. Refer to Testing and Adjusting, KENR8394, "Electronic Control Module (ECM) – Replace"

STOP
NO - The resistance is not greater than 5000 ohms. There is a short in the machine harness. The short is between ME-C2-46 (Wire 859-YL(Yellow)) and one of the grounded wires in the machine harness.
Repair: Repair the machine harness or replace the machine harness.

STOP

Test Step 7. CHECK THE SIGNAL VOLTAGE AT THE INPUT/OUTPUT MODULE (I/O MODULE)

Turn the keyswitch and battery disconnect switch to the OFF position.
Disconnect the machine harness connector from the VIMS Application Module.
Connect the J1 and J2 machine harness connectors to the Input/Output Module (I/O Module).
Turn the keyswitch and battery disconnect switch to the ON position.
At the Input/Output Module, insert 7X-1710 Multimeter Probe leads beside contact J2-16 (Wire 859-YL(Yellow)) and contact J1-21 (Wire J849-WH(White)).
Measure the voltage.

Expected Result:

The voltage is between 1.0 VDC and 9.0 VDC.

Results:

YES - The voltage is between 1.0 VDC and 9.0VDC. (Check harness and connectors. Reconnect harness connectors. Key cycle machine. Check for active diagnostics. May have been due to bad connection).
STOP
NO - The voltage is less than 1.0 VDC. Proceed to Test Step 8.
NO - The voltage is greater than 9.0 VDC.
Repair: Repeat this procedure. If the problem remains, replace the sensor. After the sensor is replaced, repeat this Test Step again. If the diagnostic code is still active, the Input/Output Module (I/O Module) may be faulty. However, I/O Module failure is unlikely. Exit this procedure and perform this procedure again. If the cause of the diagnostic code is not found, replace the ECM. Refer to Testing and Adjusting, KENR8394, "Electronic Control Module (ECM) – Replace".

STOP

Test Step 8. CHECK THE HARNESS FOR A SHORT TO GROUND

Turn the keyswitch and battery disconnect switch to the OFF position.
Disconnect the machine harness connector form the Input/Output Module.
At the machine harness connector J2, measure the resistance between connector J2-16 (Wire 859-YL(Yellow)) and all J1 and J2 contacts that are connected to ground or to frame ground.

Expected Result:

The resistance measurement is greater than 5000 ohms.

Results:

YES - The resistance is greater than 5000 ohms. The harness does not have a short to ground.
Repair: Repeat this procedure. If the problem remains, replace the sensor. After the sensor is replaced, repeat this Test Step again. If the diagnostic code is still active, the Input/Output Module may be faulty. However, I/O Module failure is unlikely. Exit this procedure and perform this procedure again. If the cause of the diagnostic code is not found, replace the ECM. Refer to Testing and Adjusting, KENR8394, "Electronic Control Module (ECM) – Replace".

STOP
NO - The resistance is not greater than 5000 ohms. There is a short in the machine harness. The short is between J2-16 (Wire 859-YL(Yellow)) and one of the grounded wires in the machine harness.
Repair: Repair the machine harness or replace the machine harness.

STOP