To self-test a Roland MT-32, turn the unit on while holding down the 3 button, Volume and turn on the unit to enter test mode. You can check all the keys and play some test tones. To test the midi, you need to have the midi cables plugged in. To play a demo song, just hold just Master Volume. The “MIDI Message” light should flicker if it receives data.

Here’s a great guide for setting up an MT-32

• MOLEX 5 Pin DIN to DB15 MIDI 92604-0001
• 3.5mm TRS to Dual 6.35mm TS Breakout Cable – 3.5mm Stereo Cable to 1/4 Y Splitter Cord