ELEMENT AS-JACKET WATER HEATER 4478618 - Caterpillar

Table 7
FMI 3 Troubleshooting
Troubleshooting Test Steps Values Results
1. Check The Sensor
Note: Refer to the tables above for a list of resistance values related to specific values.
A. Turn the key switch and the disconnect switch to the OFF position.
B. Disconnect the sensor from the harness.
C. Measure the resistance between pin 1 and 2 of the sensor.
The resistance reading agrees with the values from the table. OK: The resistance readings agree with the values in the table.
Proceed to Test Step 2.
NOT OK: The resistance readings do not agree with the values in the table.
REPAIR: Replace the sensor.
Proceed to Test Step 4.
2. Check For An Open In The Sensor Circuit
A. The key switch and disconnect switch remain in the OFF position.
B. The harness connector remains disconnected from the sensor.
C. At the sensor harness connector, install a jumper wire across pins 1 and 2.
D. Disconnect the J1 and J2 connectors from the ECM.
E. At the ECM harness connector, measure the resistance between the signal and return contacts for the sensor.
The resistance reading is less than 5 Ω. OK: The resistance is less than 5 Ω.
Proceed to Test Step 3.
NOT OK: The resistance is greater than 5 Ω. The open is in the signal circuit or the return circuit.
REPAIR: Repair or replace the harness.
Proceed to Test Step 4.
3. Check The Signal Circuit For A Short.
A. The disconnect switch and the key switch remain in the OFF position.
B. The harness connectors J1 and J2 remain disconnected from the ECM.
C. Remove the jumper wire from the sensor harness connector.
D. At the ECM harness connectors, measure the resistance between the signal circuit and all the other contacts that are used on the ECM.
Each resistance reading is greater than 5 K Ω. OK: Each measurement is greater than 5 K Ω.
Proceed to Test Step 4.
NOT OK: A resistance measurement is less than 5 Ω. A short exists between the signal circuit and the circuit with the low-resistance measurement.
REPAIR: Repair or replace the machine harness.
Proceed to Test Step 4.
4. Check If The DTC Remains
A. Reconnect all harness connectors. Return machine to normal operating condition.
B. Turn the key switch and the disconnect switch ON.
C. Clear all DTCs.
D. Operate the machine.
E. Stop the machine and engage the parking brake.
F. Check if the DTC is active.
The DTC is no longer present. OK: The DTC does not exist at this time. The initial DTC may have been caused by poor electrical connection or short at one of the harness connections. Resume machine operation.
STOP.
NOT OK: The diagnostic trouble code has not been corrected. If the DTC has not been corrected after performing the procedure a second time, the ECM may require replacement.
Prior to replacing the ECM, always contact the Technical Communicator at your dealership for possible consultation with Caterpillar. This consultation may effect repair time.
Follow the steps in Troubleshooting, "ECM - Replace" if the ECM needs to be replaced.
STOP.
Table 8
FMI 4 Troubleshooting
Troubleshooting Test Steps Values Results
1. Check The Sensor
A. Turn the key switch and disconnect switch ON.
B. Ensure that the DTC is active.
C.