Bobcat S850 D4903 Error Code
D4903 Error Code
Park Brake Reserve Pressure Valve Relay Feedback Error Off is the main cause of D4903 error.To solve D4903 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.