Operation CHARM: Car repair manuals for everyone.
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Component Test

Main Relay

EFI Main Relay Circuit Diagram:









INSPECTION OF MAIN RELAY
1. CHECK MAIN RELAY OPERATION
(a) Turn on the ignition switch.
(b) At this time an operation noise will occur from the relay.





2. MEASURE RESISTANCE OF MAIN RELAYS
(a) Remove the main relay from the relay block.
(b) Measure the resistance between each terminal.

Resistance Between Terminals:
1 - 2 60 - 80 Ohms
3 - 4 Infinity