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, located under the dash near the ECU, supplies power to the ECU, fuel injectors, various solenoid valves and air flow meter when the ignition is switched "ON." The ECU completes the circuit by grounding these devices when indicated by its calculations.