IT38G Series II Integrated Toolcarrier and 938G Series II Wheel Loader Caterpillar

Illustration 1	g00955412
Schematic for the Rotary Switch (Transmission Auto/Manual Switch)

This diagnostic code is associated with the rotary switch (Transmission Auto/Manual Switch). The rotary switch is connected to three inputs of the ECM. Two contacts are open and the other contact is grounded during proper operation.

The FMI 04 means that the ECM has determined that two or more circuits are grounded.

Note: The following test procedure may create other diagnostic codes. Ignore these diagnostic codes and clear the diagnostic codes when the original diagnostic code has been corrected. Ensure that the diagnostic code of CID 0368 FMI 04 is active before performing this procedure.

Test Step 1. CHECK THE SWITCH

1. Turn the key start switch and the disconnect switch to the OFF position.

2. Disconnect the machine harness from the switch.

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

Expected Result:

The CID 1521 FMI 04 has been replaced by CID 0368 FMI 03.

Results:

• OK - The CID 0368 FMI 04 has been replaced by CID 0368 FMI 03. The machine harness and the ECM are correct. Proceed to Test Step 2.

• NOT OK - The CID 0368 FMI 04 is still active. Proceed to Test Step 2.

Test Step 2. CHECK THE HARNESS

1. Turn the disconnect switch and the key start switch to the OFF position.

2. The machine harness remains disconnected from the switch.

3. Disconnect the machine harness connector(s) from the ECM.

4. At the machine harness connector for the ECM, measure the resistance from contact J1-29 (wire 973-BR), contact J1-31 (wire 977-YL), and contact J1-35 (wire H730-PK) of the machine harness to all the contacts that are used in the machine harness connectors for the ECM.

Expected Result:

Each resistance measurement is greater than 5000 ohms.

Results:

• YES - Each resistance measurement is greater than 5000 ohms. The ECM has failed.

  Repair: It is unlikely that the ECM has failed. Exit this procedure and perform this procedure again. If the cause of the diagnostic code is not found, replace the ECM. See Troubleshooting, "Electronic Control Module (ECM) - Replace".

  Stop.

• NO - One or more of the measurements were less than 5 ohms. There is a short in the machine harness.

  Repair: The short is between wire 973-BR and the circuit with the lowest resistance measurement, wire 977-YL and the circuit with the lowest resistance measurement, or the short is between wire H730-PK and the circuit with the lowest resistance measurement. Repair the machine harness or replace the machine harness.

  Stop.

Test Step 3. CHECK THE OPERATION OF THE SWITCH (MANUAL POSITION)

1. Remove the jumper that was installed in the previous Test Step.

2. The machine harness remains disconnected from the switch.

3. Rotate the switch to the MANUAL position.

4. Connect one lead from a multimeter to contact 1 (wire 962-OR) of the harness connector for the switch.

5. Connect the other lead from a multimeter to contact 2 (wire 973-BR) of the harness connector for the switch.

6. Measure the resistance between contact 1 (wire 962-OR) and contact 2 (wire 973-BR). Note the resistance.

7. Disconnect the lead from contact 2 (wire 973-BR) and connect the lead to contact 3 (wire 977-YL).

8. Measure the resistance between contact 1 (wire 962-OR) and contact 3 (wire 977-YL).

9. Disconnect the lead from contact 3 (wire 977-YL) and connect the lead to contact 4 (wire H730-PK).

10. Measure the resistance between contact 1 (wire 962-OR) and contact 4 (wire H730-PK).

Expected Result:

The resistance from contact 1 to contact 2 is less than 5 ohms, and the resistance from contact 1 to contacts 3 and 4 is greater than 5000 ohms.

Results:

• YES - The resistance from contact 1 to contact 2 is less than 5 ohms, and the resistance from contact 1 to contacts 3 and 4 is greater than 5000 ohms. The switch is operating correctly in the power position. Proceed to Test Step 4.

• NO - The resistance from contact 1 to contact 2 is not less than 5 ohms, or the resistance from contact 1 to contacts 3 and 4 is not greater than 5000 ohms. The switch has failed.

  Repair: Replace the switch.

  Stop.

Test Step 4. CHECK THE OPERATION OF THE SWITCH (AUTO 4-2 POSITION)

1. Rotate the switch to the AUTO 4-2 position.

2. Connect one lead from a multimeter to contact 1 (wire 962-OR) of the harness connector for the switch.

3. Connect the other lead from a multimeter to contact 2 (wire 973-BR) of the harness connector for the switch.

4. Measure the resistance between contact 1 (wire 962-OR) and contact 2 (wire 973-BR). Note the resistance.

5. Disconnect the lead from contact 2 (wire 973-BR) and connect the lead to contact 3 (wire 977-YL).

6. Measure the resistance between contact 1 (wire 962-OR) and contact 3 (wire 977-YL).

7. Disconnect the lead from contact 3 (wire 977-YL) and connect the lead to contact 4 (wire H730-PK).

8. Measure the resistance between contact 1 (wire 962-OR) and contact 4 (wire H730-PK).

Expected Result:

The resistance from contact 1 to contact 3 is less than 5 ohms, and the resistance from contact 1 to contacts 2 and 4 is greater than 5000 ohms.

Results:

• YES - The resistance from contact 1 to contact 3 is less than 5 ohms, and the resistance from contact 1 to contacts 2 and 4 is greater than 5000 ohms. The switch is operating correctly in the midrange position. Proceed to Test Step 5.

• NO - The resistance from contact 1 to contact 3 is not less than 5 ohms, or the resistance from contact 1 to contacts 2 and 4 is not greater than 5000 ohms. The switch has failed.

  Repair: Replace the switch.

  Stop.

Test Step 5. CHECK THE OPERATION OF THE SWITCH (AUTO 4-1 POSITION)

1. Rotate the switch to the AUTO 4-1 position.

2. Connect one lead from a multimeter to contact 1 (wire 962-OR) of the harness connector for the switch.

3. Connect the other lead from a multimeter to contact 2 (wire 973-BR) of the harness connector for the switch.

4. Measure the resistance between contact 1 (wire 962-OR) and contact 2 (wire 973-BR). Note the resistance.

5. Disconnect the lead from contact 2 (wire 973-BR) and connect the lead to contact 3 (wire 977-YL).

6. Measure the resistance between contact 1 (wire 962-OR) and contact 3 (wire 977-YL).

7. Disconnect the lead from contact 3 (wire 977-YL) and connect the lead to contact 4 (wire H730-PK).

8. Measure the resistance between contact 1 (wire 962-OR) and contact 4 (wire H730-PK).

Expected Result:

The resistance from contact 1 to contact 4 is less than 5 ohms, and the resistance from contact 1 to contacts 2 and 3 is greater than 5000 ohms.

Results:

• YES - The resistance from contact 1 to contact 4 is less than 5 ohms, and the resistance from contact 1 to contacts 2 and 3 is greater than 5000 ohms. The switch is operating correctly in the economy position. Proceed to Test Step 6.

• NO - The resistance from contact 1 to contact 4 is not less than 5 ohms, or the resistance from contact 1 to contacts 2 and 3 is not greater than 5000 ohms. The switch has failed.

  Repair: Replace the switch.

  Stop.

Test Step 6. CHECK IF THE DIAGNOSTIC CODE REMAINS

1. Inspect the contacts of the harness connectors and clean the 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. Determine if CID 0368 FMI 04 is present.

Expected Result:

The CID 0368 FMI 04 is active.

Results:

• YES - The CID 0368 FMI 04 is active. The diagnostic code has not been corrected. The ECM may have failed.

  Repair: It is unlikely that the ECM has failed. Exit this procedure and perform this procedure again. If the cause of the diagnostic code is not found, replace the ECM. See Troubleshooting, "Electronic Control Module (ECM) - Replace".

  Stop.

• NO - The CID 0368 FMI 04 is not active. The diagnostic code is NOT present. The diagnostic code does not exist at this time.

  Repair: The initial diagnostic code was probably caused by a poor electrical connection or a short at one of the harness connectors that was disconnected and reconnected. Resume normal machine operation.

  Stop.