Bobcat 553 H4821 Error Code
H4821 Error Code
5V Sensor Supply Out of Range High is the main cause of H4821 error.A significant number of consequences can be suffered due to an overheating engine with code H4821. The problem might be a blown gasket or something related to the fuel tank.
Tip For 553 Model
When the temperature is below -30 C (-20 F), hydrostatic oil must be warmed before starting. The hydrostatic system will not get enough oil at low temperatures and will be damaged. Park the machine in an area where the temperature will be above -18 C (0 F) if possible.