| |
| Illustration 1 | g01343739 |
|
Connections of the inching pedal switch | |
This diagnostic code is associated with the inching pedal switch. The switch is connected to two inputs of the ECM. The inputs are "Normally Open" and "Normally Closed". One of the inputs is open and the other input is grounded during proper operation.
The FMI 02 means that the ECM has determined that the "Normally Open" and "Normally Closed" circuits are in the same state.
Note: The following test procedure may create other diagnostic codes. Ignore these diagnostic codes and clear these diagnostic codes when the original diagnostic code has been corrected. Ensure that the diagnostic code of CID 1484 FMI 02 is active before performing this procedure.
Test Step 1. CHECK THE OPERATION OF THE SWITCH
- Turn the key start switch and the disconnect switch to the OFF position.
- Disconnect the machine harness connector or the wires from the switch.
- Connect one lead from the multimeter to the common contact (COM) for the switch.
- Connect the other lead from the multimeter to the normally open contact (NO) for the switch.
- Measure the resistance between contact COM and contact NO. Note the resistance.
- Disconnect the lead from contact NO and connect the lead to the normally closed contact (NC).
- Measure the resistance between contact COM and contact NC. Note the resistance.
Expected Result:
The resistance from contact COM to contact NO is greater than 5000 ohms, and the resistance from contact COM to contact NC is less than 5 ohms.
Results:
- YES - The resistance from contact COM to contact NO is greater than 5000 ohms, and the resistance from contact COM to contact NC is less than 5 ohms. Proceed to Test Step 2.
- NO - The resistance measurements do not differ. The switch has failed.
Repair: Replace the switch.
STOP
Test Step 2. CHECK THE OPERATION OF THE SWITCH
- Connect one lead from the multimeter to the common contact (COM) for the switch.
- Connect the other lead from the multimeter to the normally open contact (NO) for the switch.
- Actuate the switch and measure the resistance between contact COM and contact NO. Note the resistance.
- Disconnect the lead from contact NO and connect the lead to the normally closed contact (NC).
- Actuate the switch and measure the resistance between contact COM and contact NC. Note the resistance.
Expected Result:
The resistance from contact COM to contact NO is less than 5 ohms, and the resistance from contact COM to contact NC is greater than 5000 ohms.
Results:
- YES - The resistance from contact COM to contact NO is less than 5 ohms, and the resistance from contact COM to contact NC is greater than 5000 ohms. Proceed to Test Step 3.
- NO - The resistance measurements do not differ. The switch has failed.
Repair: Replace the switch.
STOP
Test Step 3. CHECK THE GROUND CIRCUIT OF THE SWITCH IN THE WIRE HARNESS.
- Connect one lead from the multimeter to contact COM (wire J764-BR(Brown)) of the wire harness connector for the switch.
- Connect the other lead from the multimeter to frame ground.
- Measure the resistance between contact COM (wire J764-BR(Brown)) and frame ground.
Expected Result:
The resistance is less than 5 ohms.
Results:
- OK - The resistance is less than 5 ohms. The circuit is correct. Proceed to Test Step 4.
- NOT OK - The resistance is greater than 5000 ohms. The circuit is open. The machine harness has failed.
Repair: Repair the machine harness or replace the machine harness.
STOP
Test Step 4. CHECK THE SWITCH CIRCUITS FOR A SHORT CIRCUIT.
- The disconnect switch and the key start switch remain in the OFF position.
- Disconnect the machine harness connector(s) from the ECM.
- The connector for the switch remains disconnected.
- At the machine harness connector for the ECM, measure the resistance from contact J1-31 and contact J1-30 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:
- OK - Each resistance measurement is greater than 5000 ohms. The harness is correct. Proceed to Test Step 5.
- 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 J1-31 and the circuit with the lowest resistance measurement or the short is between J1-30 and the circuit with the lowest resistance measurement. Repair the machine harness or replace the machine harness.
STOP
Test Step 5. CHECK THE SWITCH CIRCUITS IN THE HARNESS.
- The machine harness remains disconnected from the ECM and the switch.
- At the harness connector for the switch, connect a jumper wire between contact NO and contact NC.
- At the harness connector for the ECM, measure the resistance from contact J1-31 to contact J1-30.
Expected Result:
The resistance is less than 5 ohms.
Results:
- OK - The resistance is less than 5 ohms. Proceed to Test Step 6.
- NOT OK - The resistance is greater than 5000 ohms. The circuit is open.
Repair: The machine harness has failed. Repair the machine harness or replace the machine harness.
STOP
Test Step 6. CHECK IF THE DIAGNOSTIC CODE REMAINS.
- Inspect the contacts of the harness connectors and clean the connectors.
- Reconnect all harness connectors.
- Turn the disconnect switch and the key start switch to the ON position.
- Operate the machine.
- Determine if the diagnostic code is active.
Expected Result:
The diagnostic code is active.
Results:
- YES - The diagnostic code 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. Prior to replacing an ECM, always contact your dealership for possible consultation with Caterpillar. This consultation may greatly reduce repair time. If the ECM requires replacing, refer to Testing and Adjusting, "Electronic Control Module (ECM) - Replace".
STOP
- NO - The diagnostic code is not active. The diagnostic code is NOT present. The diagnostic code does not exist at this time. 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