RAIL-TOP 1408438 - Caterpillar

Table 2
Troubleshooting Test Steps Values Results
1. Identify Active FMI Code Associated With Sensor Circuit
Code present. FMI 2 diagnostic code, proceed to Test Step 2.
FMI 3 diagnostic code, proceed to Test Step 4.
FMI 4 diagnostic code, proceed to Test Step 9.
Begin Process For FMI 2 Troubleshooting HERE
2. Check The Circuit For A Short
A. Turn the keyswitch OFF.
B. Disconnect the switch from the machine harness.
C. Disconnect the J1 and J2 machine harness connections from the Machine ECM.
C. At the machine harness connector for the ECM, one at a time, measure the resistance between each of the signal contacts to every other contact used in the J1 and J2 machine harness connectors.
The resistance is greater than 5K Ω. OK - The resistance is correct.
Proceed to Test Step 3.
NOT OK - The resistance check is not correct.
Repair: There is a short in the signal circuit of the machine harness. Repair or replace the machine harness.
STOP
3. Check The Operation Of The Switch
A. The keyswitch remains OFF.
B. Reconnect all harness connectors.
C. Check the operation of the switch.
The switch operates correctly. OK - The switch is operating correctly.
Proceed to Test Step 12.
NOT OK - The switch is not operating correctly. The switch has failed.
Repair: Replace the switch.
STOP
Begin Process For FMI 3 Troubleshooting HERE
4. Check The Harness For An Open
A. Turn key start switch and disconnect switch OFF.
B. Disconnect the switch from the machine harness.
C. Disconnect the J1 and J2 machine harness connector.
D. At the machine harness connector for the switch, place a jumper wire between the two signal wires at the switch connector.
E. At the machine harness connection for the ECM, measure the resistance between the signal contact wires. (See the appropriate schematic for wire locations.)
The resistance is less than 5 Ω. OK - The circuit is correct.
Proceed to Test Step 5.
NOT OK - The resistance is greater than 5K Ω. The circuit is open.
Repair: Repair or replace the machine harness.
Note: A resistance that is greater than 5 Ω but less than 5K Ω indicates a loose connection or a corroded connection in the circuit. A resistance measurement that is greater than 5K Ω indicates an open in the circuit.
STOP
5. Check The Harness For A Short
A. The keyswitch remains OFF.
B. All harness connectors remain disconnected.
C. Remove the jumper wire installed in the previous step.
D. At the machine harness connector for the ECM, measure resistance between the signal contacts and all other contacts used in the J1 and J2 harness connectors.
The resistances are greater than 5K Ω. OK - All resistances are greater than 5K Ω. The harness circuit is correct.
Proceed to Test Step 6.
NOT OK- The resistance less than 5 Ω.
Repair: A short exists in the harness between the signal circuit and the wire with the low-resistance reading. Repair or replace the machine harness.
Note: A resistance that is greater than 5 Ω but less than 5K Ω would indicate a loose connection or a corroded connection in the circuit. A resistance measurement that is greater than 5K Ω would indicate an open in the circuit.
STOP
6.