15Trouble ShootingFault Possible Cause RemedyNo operating functions; all LEDdisplays darkMain cable not plugged in Plug in main cableSocket dead Check socket and fuseMain cable damaged or interrupted Replace main cableFaulty electronics Return unit to supplier ormanufacturerNo ultrasound; LED displayultrasound darkTurning knob for ultrasound inposition, O” Switch on ultrasound at turning knobUnit is switched Switch on the unit at on/off keyKey (ultrasound) not pressed Switch key onFaulty electronics Return unit to supplier ormanufacturerNo ultrasound; LED displayultrasound is blinking rapidly = faultindication ultrasoundUnsuitable filling level Change filling level, switch unit offand onFaulty electronicsSwitch unit off and on if fault occursagain: return unit to supplier ormanufacturerCleaning result not satisfactoryPossibly no cleaning medium orwrong cleaning medium used Use suitable cleaning mediumPossibly cleaning temperature notsuitable Change temperaturePossibly cleaning period too short Repeat cleaning interval