The S1 Cafe - Helping Your Espresso Dreams Become Reality

I've been a lurker for a few weeks now, but nothing that I've searched is related to the issues I'm seeing, so I figure I'll post.

Bought the used machine about a month ago S/N 275799 3/21 manufacture date. It came from a little coffee shop, the machine was not working and someone had already removed the side panels, but it didn't look like they'd gone any further. Previous owner stated that they thought it had "control board issues"

The interior of the machine looks clean, no corrosion or moisture issues.

The machine seems to be getting power, the LUCCA on the front lights up, but nothing else happens, the power button does not do anything.

All fuses check out good, I checked the main fuse underneath and the fuse on the control board, both visually and with a multimeter. The machine is feeding power in to the control board, and the faceplate buttons and ribbon cable have continuity when buttons are pressed (checked with multimeter) across the pins.

None of the components on the faceplate look damaged or burned, and none of the components on the control board look damaged or burned, there is no corrosion and most every component on the board was checked for continuity. The micro relays test out good, and so do the varistors (only checked on the board, did not desolder)

Is there anything else I should be looking for, do these control boards go bad and is there any service documents on how to test them to verify. (Control board has pinouts for "Service")

Also, I understand that the control board is around $500 USD, so if mine is bad, can I diagnose and repair it. I can solder/desolder adequately, and I have the basics of electricity, with the knowledge of the internet search engine.

Thanks in advance, I don't have much money into this machine, so I'm willing and ready to tinker.

3) Press the ON / OFF (27) and button and keep it pressed for about 3 seconds,
the green On/STBY light (22) changes from flashing to steady indicating the
machine is ON. At the same time the lights from (14) to (21) turn on steadily for
about a second (indicating power on test mode).

Did you try the above from the User's Manual and nothing happens?

Yeah, I tried that, I don't see any other lights than the backlit LUCCA that light up when the machine is plugged in. Pressing the power button, or any button for any length of time dosen't do anything.

There's ribbon cable that goes between the front panel and the control board. Be sure it is plugged in well on both ends.

Ribbon cable is plugged in and I checked the continuity across each male end of the cable when it was disconnected.

I've never owned a Mini nor heard of anyone with your specific issue. Before you replace or work on the control board, you should talk to some Mini owners to see if there are any Mini specific issues that might cause this problem.

There was one other guy on this Forum who had a control board issue that he was able to troubleshoot and repair, but it wasn't just a dead unit. The control board is usually not the issue, but there's always a first time.

Hey Chas, thanks for the info. I got a hold of a copy of the control board instructions, and it outlines the dipswitch settings.

If I understand the settings correctly, the control board can be used for 5 different production models, and by setting the dipswitch settings all to "Off" or two or more set to "On" the control board should show a fault and that fault will flash on the display panel lights.

When I set the dipswitches to all "Off" and try to power on the machine, nothing happens.

Since I tested the "power on" switch on the display panel and it has continuity when I press it down and hold for 3 seconds, this would lead me to say the control board is not functioning.

With all the dipswitches "Off" the control board shouldn't care about the status of any of the inputs or outputs (since it wouldn't know what production model machine it was) and it would only display a fault code.

I've decided to order a control board, so we'll await for it to arrive and then proceed.

New control board arrived and I installed it. The machine started right up and seems to be working as designed. So the issue was definitely the old control board was fried.

This may help other people, if you need to troubleshoot the control board and it's the board with dipswitches, switch them all to "off" and try to power on, with no dipswitches set, the control board won't know what type of machine it's trying to control, so it won't matter if other components (like boiler, etc) are bad with the dipswitch settings all "off" the control board ignores the components in the machine and will flash an error code on the panel. If nothing happens (no indicator lights on the panel, no reaction from the machine) the board may be dead.

The control board was about $450 USD from Chris Coffee, it shipped quickly and was wrapped wonderfully.

The grouphead was filthy and the gasket brittle and cracked, so I went ahead and ordered those, now that the unit is back working.

You have the unique experience of being the first one in 15 years to require a new controller board.