COVER-FRONT 3718057 - Caterpillar

Illustration 1 g02148563
Connections of the seat sensor
This diagnostic code is associated with the operator presence sensor in the seat. The FMI 03 is recorded when the voltage in the circuit is above normal.The possible causes of this diagnostic code are listed below:
The return circuit is open.
The supply circuit is shorted to the battery.
The harness has failed.
The ECM has failed. An ECM failure is unlikely.
Table 1
Sensor Status
MODE Resistance Voltage seen by ECM
Operator present 90 to 800 ohms 0.2 to 2.93 VDC
Operator not present 800 to 4000 ohms 2.93 to 4.95 VDC Note: The following test procedure may create other diagnostic codes. Ignore these created diagnostic codes and clear these diagnostic codes when the original diagnostic code has been corrected. Ensure that the diagnostic code of CID 2113 - FMI 03 is active before performing this procedure.Test Step 1. Check the harness for an open circuit.
Turn the key start switch and the disconnect switch to the OFF position.
Disconnect the machine harness connectors from the ECM.
Disconnect the 2-pin connector for the sensor from the seat.
Connect a jumper wire to contact "1" wire (U767-BU(Blue)) and contact "2" wire (L740-BR(Brown)) of the connector for the seat.
At the connector for the ECM, measure the resistance between contact J2-22 wire (L740-BR(Brown)) and contact J1-53 wire (U767-BU(Blue)). Expected Result:The resistance should be less than 5 ohms.Results:
YES - The resistance is less than 5 ohms. Proceed to Test Step 2.
NO - The resistance is greater than 5 ohms.Repair: The open connection or the poor connection is in wire (L740-BR(Brown)). Refer to Electrical System Schematic, KENR8916 of the machine. Examine all of the connectors for possible locations of an open. For information on testing for open circuits and finding open circuits, refer to Troubleshooting, "Wiring Harness (Open Circuit) - Test". Repair the machine harness or replace the machine harness.STOPTest Step 2. Check the supply circuit for a short to the battery.The 2-pin connector remains disconnected from the seat. The disconnect switch and the key start switch are in the OFF position.
Connect the J1 and J2 machine harness connectors to the ECM.
Use a wire removal tool in order to remove contact J1-53 wire (U767-BU(Blue)).
Turn the disconnect switch and the key start switch to the ON position. Do not start the engine.
Measure the voltage from wire U767-BU(Blue) to a clean source of frame ground. Expected Result:The voltage measurement is 0 VDC.Results:
YES - The voltage measurement is 0 VDC. Proceed to Test Step 3.
NO - The voltage measurement is greater than 0 VDC.Repair: There is a short circuit in the harness. The short is between wire (U767-BU(Blue)) and the wire with the low resistance measurement. Refer to Electrical System Schematic, KENR8916 of the machine. Examine all of the connectors for possible locations of a short. For information on testing for short circuits and finding short circuits, refer to Troubleshooting, "Wiring Harness (Short Circuit) - Test". Repair the machine harness or replace the machine harness.STOPTest Step 3. Check the status of the diagnostic code.
Inspect the harness connectors. Clean the contacts of the harness