[SOLVED] Diagnose my starter problem please

[keratos]

Intermittent faults are a nightmare. All you can do to pinpoint it is to ignore the results you get when it's working OK and concentrate on those you get when in faulty mode.
Perhaps the next step is to try a voltage reading on the starter motor itself to eliminate the cable and connectors from the relay as being the cause.

Yep. But as above... I shorted the battery and relay output (to motor) and all is fine so it's not the cable from relay to motor