CHAPTER 2 DIAGNOSISTABLE 2-5. BALANCE CANNOT CALIBRATE INTERNALLYSYMPTOM PROBABLE CAUSE REMEDYBalance can be turned onbut will not calibrate usinginternal calibration.Balance may beunstable.The InCal WeightHardware may be dirty,mis-aligned ordefective.Calibration MotorAssembly may bedefectiveMain PC Board may bedefective.Load Cell PCB isdefectiveLevel the balance using levelingfeet on rear of chassis, togetherwith leveling bubble, just insidethe left Door Side Draft Shield.Disassemble the InCal WeightHardware and test it.->InCal Weight HardwareDisassembly & Testing 3.1.4.If there are problems with theWeight Arm movements, checkthe Calibration Motor, andreplace if necessary.->Removing & ReplacingCalibration Motor Assembly3.1.5.Verify that all other functionsare operational. If not, the MainPC board may be defective.->Main PCB Removal &Replacement 3.1.3.Replace Load Cell PCB.(See p. 3-27.)Discovery Balance Service Manual 2-5 Ohaus Corporation www.ohaus.com
