2006-2008 Polaris Snowmobiles FS/FST Service Manual., Page 283Get this manual
Chassis Electrical System EFI Relay Circuit
The EFI relay is the primary or "main" relayIf the EFI relay fails, the ECU will never power-up and the engine will not startWhen closed by the ECU, the EFI relay supplies battery voltage to the "EFI Bus" circuitsThese circuits include: 20A Ignition Relay Power
20A EFI System Power 20A LambdaMFD Power
Ignition Relay Control Circuit