CPU board repairs


So I’m still screwing with this old robot controller…was able to get it to power up under normal operating conditions and got the monitor working…anddddd…no signal. The CPU board has a CPU and a sub CPU and both have indicator lights which are supposed to denote a halt condition following power up…I think both lights used to light but now only one. I discharged myself removed the board and reseated the cpus…now no lights and a hard fault on the io module denoting a fatal CPU error. My theories are such. 1. Despite my best efforts I esded the board. 2 caused physical damage to the cpus. (They were REALLY in there) 3 messed up the board by checking components on it with a dmm ( though rather unlikely) or 4 which is what I’m hoping for ancient solder joints have unseen faults and stress from CPU removal exacerbated these. So now my only option is a reflow …how should I go about doing this ( also all of the lead solder joints are corroded and need to be deoxidised somehow) also the board is irreplaceable $400-$2000 which is to much for me to spend if in still not sure it will work. If this reflow doesn’t work ill pull all the guts and forget about them and move for full steam ahead with STMBL just trying to work with what I have first.





through hole solder joints degrading like that sounds quite unlikely… can you replace the CPU chips from ebay or similar?



No main is fanuc ASIC and the others I haven’t be able to find this unit was built in 1986



Do you have part numbers? There seem to be a fair number of similar vintage, e.g. https://www.ebay.com/itm/Fanuc-A16B-1211-0041-06A-Robot-Control-Cpu-Board-A16B12110041-06A-Used-001/113186714040



It’s a16b-1210-095 I haven’t been able to find anything for as reasonable a price as you posted



how bout this

or this

oh or this

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Lol point taken thanks very much for your help



thanks very much again my problem was i had been searching ebay on my phone and it only gave me the most expensive option for some reason. ive since bought a replacement board though havent installed it yet because i have to deal with some other problems on it now.