Bobcat S850 W4903 Error Code
W4903 Error Code
Blue lights Output Short To Ground is the main cause of W4903 error.To solve W4903 locate and open the low-pressure valve, then attach the refrigerant to the valve and charge from there. Ensure you use the right refrigerant type and amount, as specified by a manufacturer. It is possible to overcharge the AC, so consider seeking help from a mechanic.
Tip For S850 Model
It is recommended in cold weather to cycle the glow plugs twice before attempting to start the engine. This will allow for additional heating time for cold weather starting.