The screen needs three power connections: a permanent 12V feed direct from the battery, a switched ignition feed, and a clean chassis ground. All three are required. The screen will not behave correctly on ignition power alone.
The permanent feed is what allows the fast boot behaviour. Without it the screen cold boots every time you turn the key and you wait several seconds for a cluster that should be instant.
Annotated wiring diagram showing the three power connections at the harness connector, with wire colours and pin numbers labelled directly on the image.
Final harness wire colours and pin numbers for E-10 and E-12, plus the recommended fuse rating for the permanent feed.
⚠️ Fuse the permanent feed at the battery. An unfused permanent 12V run through a vehicle interior is a fire risk, and it is the first thing an insurer looks at.
Related: Why Your Screen Needs Permanent Battery Power · My Screen Does Not Turn On · My Screen Stays On After I Turn Off the Ignition
