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| Illustration 1 | g01268293 |
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Operator Present Switch connections | |
This diagnostic code is associated with the operator present switch. The switch supplies two, switch to ground type inputs to the Implement ECM and to the Transmission Chassis ECM. The ECM expects one of the two switch inputs to be grounded at all times. When the ECM detects that both of the switch inputs are grounded at the same time, the ECM will activate an FMI 04 diagnostic code for voltage below normal.
Some conditions that can cause this diagnostic code are listed:
- One or both of the switch inputs is shorted to a ground source.
- The switch has failed.
- The ECM has failed. This is unlikely.
Note: Before performing this procedure, inspect the harness connectors that are involved in the circuit. Poor connections can often be the cause of a problem in an electrical circuit. Verify that all connections in the circuit are clean, secure and in good condition. If a problem with a connection is found, correct the problem and verify that this diagnostic code is active before performing this procedure.
| Operator Present Switch Contact States | ||
| Operator Status | N/O Input J1-64 (wire U767-BU(Blue)) | N/C Input J1-63 (wire U766-BR(Brown)) |
| Operator Not Present | Open(1) | Closed(2) |
| Operator Present | Closed | Open |
| (1) | Open to ECM return J1-23 (A295-BK(Black) - ground). |
| (2) | Closed to ECM return J1-23 (A295-BK(Black) - ground). |
Note: The operator present switch provides two inputs to the Implement ECM and to the Transmission Chassis ECM. If one ECM has activated the diagnostic code and the other ECM has not activated the diagnostic code, most likely the switch is operating correctly. This condition would indicate that there is a problem in the machine harness. In either case, perform this procedure in order to find the cause of the problem.
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.
Test Step 1. CHECK THE SWITCH
- Turn the disconnect switch and the key start switch to the ON position.
- Ensure that the diagnostic code is active.
- Observe the status of the diagnostic code while disconnecting the switch connector from the machine harness.
Expected Result:
The CID 2113 FMI 04 diagnostic code will remain active if the switch is not the cause of the diagnostic code. The switch is the cause of the diagnostic code if the CID 2113 FMI 04 diagnostic code is NO longer active and a CID 2113 FMI 03 diagnostic code becomes active.
Results:
- OK. - The CID 2113 FMI 04 diagnostic code remains active. The switch has not failed. Proceed to Test Step 2.
- NOT OK. - The CID 2113 FMI 04 diagnostic code is NO longer active. A CID 2113 FMI 03 diagnostic code becomes active when the switch connector is disconnected. The machine harness and the Implement ECM are operating correctly. The switch has failed.
Repair: Replace the operator present switch. After replacement of the switch, verify that the operation of the new switch is correct before operating the machine.
STOP
Test Step 2. CHECK THE HARNESS FOR A SHORT
The switch remains disconnected from the machine harness.
- Disconnect the machine harness connectors J1 and J2 from the Implement ECM.
- At the ECM machine harness connector J1, measure the resistance between contact J1-63 (wire U766-BR(Brown)) to frame ground. Measure the resistance between contact J1-63 (wire U766-BR(Brown)) to all of the other contacts that are used in the J1 and J2 connectors for the ECM.
- At the ECM machine harness connector J1, measure the resistance between contact J1-64 (wire U767-BU(Blue)) to frame ground. Measure the resistance between contact J1-64 (wire U767-BU(Blue)) to all of the other contacts that are used in the J1 and J2 connectors for the ECM.
Expected Result:
Each resistance measurement is greater than 5kΩ.
Results:
- OK. - Each resistance measurement is greater than 5kΩ. The switch input circuits are not shorted in the machine harness. Proceed to Test Step 3.
- NOT OK. - One or more of the resistance measurements is less than 5kΩ.
Repair: A switch input circuit is shorted to the circuit with the low resistance measurement. Refer to the complete machine Electrical System Schematic. Check the connectors that are in the involved circuits. Verify that all connection points for the circuit are clean, secure and in good condition. Repair the machine harness or replace the machine harness.
STOP
Test Step 3. CHECK THE STATUS OF THE DIAGNOSTIC CODE
- Inspect the harness connectors and clean the contacts of the harness connectors. Check the wires for damage to the insulation that is caused by excessive heat, battery acid, or chafing.
- Perform a
45 N (10 lb) pull test on each of the wires that are associated with the switch circuit. - Reconnect all harness connectors. Make sure that the connectors are fully seated and the clips for each connector are completely fastened.
- Turn the disconnect switch and the key start switch to the ON position.
- Operate the machine.
- Determine if the CID 2113 FMI 04 diagnostic code is active.
Expected Result:
The CID 2113 FMI 04 diagnostic code is not active.
Results:
- OK. - The CID 2113 FMI 04 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 2113 FMI 04 diagnostic code is active. The diagnostic code has not been corrected.
Repair: Check the circuit again. Use the Caterpillar Electronic Technician (ET) service tool, if available, in order to perform a "Wiggle Test" on the machine wiring harness. The wiggle test can detect momentary or intermittent shorts or opens in the machine wiring harness.
If the cause of the problem is not found, the ECM may have failed. Prior to replacing an ECM, always contact your dealership's Technical Communicator for possible consultation with Caterpillar. This consultation may greatly reduce repair time. If the cause of the diagnostic code is not found, replace the ECM that has activated the diagnostic code. Refer to Testing and Adjusting, "Electronic Control Module (ECM) - Replace".
STOP