Possible Solution for ERR 6 on 5424/5424R...

BOTTOM LINE UP FRONT: Raise the internal magnetic lid sensor up closer to the lid. I just received two 5424R centrifuges (with keypads instead of knobs) with ERR 6 issues into our repair shop. I opened them up and checked the braking resistors, which were both good. I cleaned and burnished all the mains power connections from the outside plug connection to the main board (unbelievably, this occasionally fixes problems in some bigger, older Eppendorf centrifuges). If I could get the centrifuges to run, I noticed that bumping them on the right side could cause an ERR 6 fault. I walked through the secondary customer support menu with Eppendorf tech support. The final code of 9: E 6 2 07 pointed to (in order): 1 - Lid switches 2 - Frequency converter board. So, after bumping the lids around some, I determined that the magnetic lid proximity sensors were causing the problem. Playing with a magnet, I discovered that there is a kind of "Goldilocks zone" where the lid internal lid sensor will throw a ERR 6 code instead of a LID ERROR code. I shimmed both of the internal lid sensors higher towards the lid with two washers (˜2 - 3 mm) and it solved the problem. After multiple spin cycles at different speeds and hard bumps on the sides and lids, I could no longer make them fail.