SIP speedo - on and of and on and off

I have done a bit of work on a mate’s scooter but now the SIP speedo is playing up. I have tidied a lot of power cables but not played with the SIP speedo cabling.
When the engine is running, the SIP speedo come on for a couple of seconds, and then off for a couple of seconds and then on again and then.....(repeat). The on and off seems very regular, not just a loose wire.
When the engine is off, the SIP speedo does not do this.
It is a six pole DC system that worked previously.
Any thoughts?
When the engine is running, the SIP speedo come on for a couple of seconds, and then off for a couple of seconds and then on again and then.....(repeat). The on and off seems very regular, not just a loose wire.
When the engine is off, the SIP speedo does not do this.
It is a six pole DC system that worked previously.
Any thoughts?