Since I bought the KL 88 Keyboard a few weeks ago I’ve been struggling to get the sustain and expression pedals working properly. I have a new half pedalling Yamaha sustain pedal, and according to Arturia, I have to plug it into the expression pedal jack to activate the half pedal function. Then for the expression pedal to work, I need to plug that into the auxiliary jack. Why Arturia haven’t fixed this with a software update I don’t know. I’ve been looking for instructions but I’ve found none (including the Arturia FAQ) that work properly. Has anybody with one of these keyboards worked out how to set it up? I’d appreciate some help if it is available. The main problem for me has been getting the keyboard to boot up with the settings intact. Help needed please😊
Currently, I do not fully understand your problem.
Could you please describe, exactly what you are doing, what behavior you experience and how that differs differs from what you would expect?
Ok. I bought a Yamaha FC3A sustain pedal so I could do half pedalling. The FC3 is the recommended pedal from Arturia. When I plug it into the the sustain input on the KL88, I can get the half pedalling working but it is reversed i.e. sustaining when up instead of down. If I try to invert it, the half pedalling option vanishes from the options. I emailed Arturia and their answer was to plug the pedal into the expression input, but this didn’t work for me either. Also, I can’t save the settings so that the keyboard boots up with my modified settings in place. So, I need to know two things:
1 How to setup the the KL 88 so that the sustain works correctly
including half pedalling
2 The correct sequence for saving the KL 88 settings so that it boots
up with the sustain pedal working as it should.
I also have a problem with the expression pedal not working correctly, but that may be that I’m using the wrong pedal. I’m more concerned about the sustain pedal settings at this stage.
Many thanks for your offer of help.
Thanks for providing more details 
Some things upfront:
- Now it is clear that your problem only concerns the use of the Keylab with a specific pedal and is unrelated to Gig Performer itself. As in my experience, this is a very friendly and helpful community, you‘ll get some help here, but I‘m not sure if we have any Arturia hardware experts here. You‘re more likely to talk to those on channels dedicated to Arturia stuff. I‘m not saying you must or should not post it here but also do not be disappointed if you don‘t find the right people here
- To make your topics on this forum easier to find, it is helpful to post them into the appropriate category, which would be Hardware. Seems banal but actually helps people orient
- I assume you‘re talking about the Keylab 88 mk2, right?
Now, regarding your two questions:
What is the behavior when you plug the pedal in the Expression port?
Of course, there are workarounds to this, either in hardware (using a polarity adapter, resolder the wires in the FC3A, use another pedal type) or in software (using Gig Performer to transform the reverse sustain input, similar to this: Next/Previous Rackspace double jumps - #4 by ezraherman)
But it’s frustrating that this is actually a problem with a MIDI controller released in 2019 
Did you try to save your settings as a user preset?
I’ve moved this discussion to “Hardware” but yeah, Simon is right, you probably need to get some Arturia experts for this one.
Thanks for the input. It seems to be a major problem as several people on the Arturia forum asked about the same issue. Doesn’t seem to be any easy answers for this. I asked on this forum because I thought others here owned the same keyboard.
I have solved this problem. Step one was to reverse, then re-solder the wires to the potentiometer and this corrected the sustain working in reverse. And the second step was to save directly to the keyboard as a preset rather than use the Midi Control Centre as provided by Arturia. All is good now.
I know that you have solved your original problem three years ago. Just would give some feedback on the MIDI Control Center thing. I bought my Keylab 88 this winter, and also have had trouble quite understanding how to use MCC for saving settings to the keyboard.
Looking closer into it yesterday, I found that if you change you settings in MCC, then click Save As…, you can give a settings template a name, in my case Gig Performer.
Having this template selected in the Templates window, and User 1 selected in the Memory window, i clicked Store To.
Now, when I select User preset 1 on my keyboard, it says Gig Performer and contains my template settings.