The battery is connected but the kit has no powerUpdated 6 months ago

Make sure that the LED or LCD display is connected properly.
If you have an LCD display (SW900 or S830) hold the “M” button pressed for 5-6 seconds to turn the kit on and off.
Check the battery connection carefully, make sure it has a positive connection.
Check if the battery has an on-off switch on it and make sure it’s switched on.
Reconnect the harness cable (the cable that splits into 4 connectors) pushing firmly.