Steris V116 S2 failed to engaged.
1) try using another coil on the S2 valve - the fact that the coil led did not light may indicate a failure of the coil or circuit board built into the coil
2) if the new coil fails to light, try looking at the driver chip for this valve - it is U16 on the I/O PCB - I believe it is replacable and has a part # of 129367-542
Hope this helps - if you need further info feel free to contact me directly at RPI 800-221-9723 EXT 1127
Yeah been through that. It sucks. Given your process so far: if you have another machine nearby, swap the I/o board. Still happening?, swap coil with any other similar valve. Still happening?, the board in the back of control box whose technical name escapes me, the board you plug control and I/o into, must be the problem. I've got a bunch of used ones you could try, all good, doesn't matter the model/size only same era. Unfortunately I'm out of town for a few days. But if you have another 116 nearby you have what you need to troubleshoot, except the board I'm talking about, too much of a hassle. Back on Tuesday. Good luck.
Sorry, also because it's easy enough swap out the valve wiring harness, do so.
Once you eliminate the impossible, whatever remains, no matter how improbable, must be the truth. According to Sherlock anyways.
Did you check the fuses drivers I/O boards? Do you have voltage at the coil?
Thank you all for quick responses.
@ Neil Blagman, replaced coil, swap I/O board with no luck.
@Bob, it's kind of puzzled me how to get to back of the board, any advice on how to remove that board?
@Cbet_Matt, there was no juice on that.
Is it possible the problem come from power board? or is it like Bob said the problem is on the back of I/O Board?
The connector board in the back of the control box could be the problem, but are LS1 (door closed) and PS1 (door sealed) closed when you are trying to manually activate S2 in service mode? Also check continuity between coil plug and cannon plug on the back of the control box.
Did this problem originate during a cycle? What was the alarm / failure?
The back board is a major pain. It involves removing the entire control box. All the screws holding sockets etc.
last resort kind of thing. I've only seen a few go bad since they were introduced in 90's. But it's certainly possible.
Sorry, did you check for voltage at valve. If no, did you check for voltage at pin socket in back of control box?. If no and output is lit, unfortunately it's probably the back board given that you've swapped out I/o. Make sure the I/o board is pushed all the way in and snapped into place.
the replacement of the back board is a pain but not as bad as I'm making it sound. It's just a process disconnecting all the wiring harnesses etc. you don't necessarily have to remove mounting brackets
if it were me I'd start at the very beginning again and be sure I've eliminated all the easy stuff one last time, power at valve, power at socket, output lit. Good luck.
Do you have power to your boiler control? If so I'm not so sure you would have an issue with your mother board. Can you activate any solenoids for the service menu I/O control?