Sim-Panel Classic Button Box
3 Stars
3 Stars

The Sim-Panel Classic Button Box from Appcentrix LLC, is a USB connected, Arduino controlled, button box specifically designed for SCS’s American Truck Simulator and Euro Truck Simulator 2. It features stainless steel push buttons, fully color-customizable LED backlighting, two programmable auxiliary buttons, and can come with or without a CB microphone.

LED Color Memory Issue

Sim-Panel Classic Button Box.

Overall, the button box has been troublesome for me. I purchased my unit in early January, 2021. The first unit had a bug in the firmware where my LED color choices would reset back to defaults on reboots. I emailed Appcentrix and was able to work with their software developer (I’m a sys admin and coder too!) to find the bug and fix the problem. They sent me an updated firmware for the unit within a few months and this fixed the issue.

Key Switch Issue

Faulty ignition switch.

However, a few months later, I started having problems with the starter key switch. Starting in the ‘Off’ position, turning the key to the ‘Power On’ position would work almost every time. However, turning the key to the ‘Start’ position would simply kill the power to the truck and move the virtual key back to the ‘Off’ position in the sim instead of starting the truck! Sometimes it would work as intended, most times not. I contacted Appcentrix about the issue and they had me send my unit in for a replacement free of charge. I’m still using this second replacement unit.

The LED color settings have been rock solid on this replacement unit which is great. Once you set the button colors to your liking, they stay. Unfortunately, the key switch on the replacement unit, which had been solid for a while, is now showing the same problem as before: sometimes the truck starts, sometimes it switches the power off.

Sim-Panel Classic Button Box.

When the key switch does this, the sim and the button box are now “out of sync” with each other. The sim shows the key switch in the ‘power off’ state but the button box is in the ‘power on’ state. The fix is to either hit ‘esc’ to show the game menus, move the button box key switch back to the ‘off’ position so that the game and the button box are now back in sync with each other, and then ‘esc’ back into the sim and try again, OR if you have the game console option turned on you can hit the tilde ‘~’ key to bring up the console, sync the button box, and then ‘~’ back in. The latter is a bit quicker than loading the menus but both work equally well.

A few other things to mention. The rocker “window switches” used to roll the power windows up and down are pretty hard to press! They feel like they stick hard in the middle position and it takes considerable effort to break past this and push the switch to the up or down position.

Noisy Buttons

Metal buttons.

The button box had always made a rattling noise when moved or shaken. At first, I thought the rattling was the metal button caps against the metal button housings that made all the racket. Before I purchased the motion rig, I was using the button box mounted to my desk so this button rattle was minimal and didn’t bother me. However, once I mounted it to the motion rig, this thing made a ton of noise! Every movement or vibration in the rig returned a chorus of high-pitched rattles from the button box and after a short bit, became unacceptable. I had to find the issue and resolve it!

Tightened button housing nuts.

In order to isolate what was rattling, I put electrical tape across all the buttons in order to stop the button tops from clinking on the button bases and tested. This made no difference at all! The rattling had to be coming from within. So, I opened the button box up and found that none of the nuts holding the button housings to the front plate had been tightened down! All 10 buttons had loose nuts inside the box making one a hell of a racket! Since the button switches are soldered directly to the main board, and I would have to unsolder every button and switch from the main board to fully access these nuts to tighten them down, I resorted to finger-tightening them as best I could and adding Locktight to the threads to keep them quiet! It worked and the button box is quiet for the first time in it’s life.


This button box retails for $249.95, but you can usually get it on sale for $199.95. Considering the firmware update needed to get the LED lights to work as advertised, two faulty ignition switches in two different boxes, and questionable build quality, all within the first year, it’s really hard for me to recommend a button box from Appcentrix. If you decide to get a button box from Appcentrix, I hope your experience is better than mine.