Manuals through 2025 now available!

Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.

LEMON is the spiritual successor to CHARM, I recommend you try it!

Link: lemon-manuals.la or lemon-manuals.org.ua

(Some people have issue connecting. LEMON is investigating. For now, use Firefox or change your DNS server)

Or, hide this message: temporarily or permanently

Main Relay (Computer/Fuel System): Description and Operation

The main relay is turned ON and OFF by turning the ignition switch ON and OFF. The power for the entire EFI system is turned ON and OFF by turning the main relay ON and OFF. The same part is used for main relay and fuel pump relay. Between the two relays installed to the bracket, the one used for the main relay is not specified. Therefore, identify it by color of lead wire (Black/White, White/Blue, White/Green).