BLOCK 8M4890 - Caterpillar

Table 3
FMI 12 Troubleshooting
1. Check if other CAN related codes are present.
A. Use the monitor or Cat ET to see if any other CAN related codes are present.
No other codes are present. OK - No other codes are present.
Proceed to Test Step 2.
NOT OK - Another CAN related code is present.
Repair: Troubleshoot the other code and repair as necessary.
Proceed to Test Step 3.
2. Check sensor power and ground.
A. Unplug the harness connector from the sensor.
B. With the keyswitch in the ON position, use a voltmeter to check for the voltage at the connector.
The voltage is approximately 24V. OK - The harness is supplying the sensor with power and ground.
Repair: Replace the sensor and proceed to Test Step 3.
NOT OK - The sensor is not getting power.
Repair: Check the fuse, and check the harness for an open. Repair or replace damaged components.
Proceed to Test Step 3.
3. Check If The Diagnostic Code Remains
A. Reconnect all harness connectors. Return the machine to normal operating condition.
B. Turn the key start switch and the disconnect switch ON.
C. Clear all diagnostic codes.
D. Operate the machine.
E. Stop the machine and engage the safety lock lever.
F. Check if the diagnostic code is active.
The diagnostic code is no longer present. OK - The diagnostic code does not exist currently. The initial diagnostic code 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 diagnostic code 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.