SPRING 1927669 - Caterpillar

Which Generate This Code:The CID 3479 FMI 04 diagnostic code is associated with "Left Front Tire Pressure" sensor. The FMI 04 diagnostic code means that the ECM has determined that the voltage of the pressure sensor is below normal. The voltage is supplied by a battery that is contained within the sealed case of the sensor. When the voltage from the battery is low, the sensor will no longer operate. The pressure sensor sends a wireless signal to the "Tire Monitoring Module". The Chassis ECM monitors the condition of the pressure sensors via a data link connection to the Tire Monitoring Module.Test Step 1. REPLACE THE WIRELESS SENSOR
The sensor and battery are contained inside of a sealed unit. The case of the pressure sensor cannot be resealed. The entire sensor must be replaced when an FMI 04 diagnostic code is recorded by the Chassis ECM.Expected Result:Replacing the wireless has corrected the FMI 04 diagnostic code.Results:
OK - After the sensor is replaced the tire monitoring system must be reset.Repair: The reset must be performed in order for the tire monitoring module to be able to identify each of the sensors. See System Operation, Test and Adjust Manual, KENR9295 for instructions on identifying the tire sensors.STOP