Keys to activate service (test) mode?

[Saxifraga]

Hi. Does anyone know which buttons to press to boot into service & test mode on the System-8?
Fantom G and all my other Roland synth have a key combination i need to hild while booting the machine.
I need to recalibrate the Pitch Bender.
thx in advance

[Saxifraga]

And once again I answer my own question in case somebody got the same problem in the future .. if there is a future.
Pressing the 01, 03 & 05 button of the sequencer while booting the SYS8 starts selftest mode. Just like the JD-Xa!