Operation CHARM: Car repair manuals for everyone.
Home >> Lexus >> 1993 >> LS 400 V8-4.0L (1UZ-FE) >> Repair and Diagnosis >> Powertrain Management >> Relays and Modules - Powertrain Management >> Relays and Modules - Computers and Control Systems >> Main Relay (Computer/Fuel System) >> Description and Operation
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


PURPOSE
The Electronic Fuel Injection Main Relay serves as a source of battery power for the Engine Control Module (ECM).

OPERATION
The EFI main relay is energized by a signal from the Ignition Switch. It then supplies battery current from the EFI fuse to the ECM.
pro multis · About Operation CHARM