First check the suitability of the power supply components of electronic scales. To do this, carefully remove the weights case. Remove the batteries, check their work on another electronic device (obviously working). If it is in a dead battery, just replace them with new ones.
Look at the ribbon cable that connects the fee scales and the display. He may loosely join them, which is the cause malfunction of the device. You need to raise the fee and press it firmly to the display. To do this, take a small wooden block, place it between the motherboard and the bottom case.
Please note to contact the ends of the scales, (pressing on them) tightly adjoin special legs weights. From the frequent use of metal contacts can shrink and scale will generate an error. Find the right size relay, replace it contacts, then attach them to the wires (better than solder).
Clean electronic scales. Gently remove the particles of food in the kitchen scales or the dust on the floor, trapped inside in the process. Wipe the scale dry with a towel, if accidentally they hit the water. It is likely that this was the cause of the failure. Keep in mind that electronic scales show inaccurate weight, if weighing value exceeds the norm.
Calibrate the balance. To do this, press the button and hold until until the display appears CAL (over 30 seconds). It should then display the digital value of the mass, which will be calibrated. As a reference, you can use any object, which specified the exact weight. After a few seconds the display will show the word PASS. The calibration has been completed. Remove the display and turn off the scale. If the calibration fails, the message will appear to FAIL. Retry the operation.