Operation CHARM: Car repair manuals for everyone.
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

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Micro ISO Relay: Testing and Inspection

Terminals:






Using 73 Digital Multimeter, check for the continuity between Terminal 2 and all other terminals. If the resistance is 5 ohms or less between Terminal 2 and any other terminal, install a new relay. If the resistance is greater than 5 ohms, continue with the test. Using two jumper wires, connect relay Terminals 1 and 3 directly to the positive battery terminal. Using 73 Digital Multimeter set in the volts position, check for voltage at Terminal 4. If battery voltage is not indicated, install a new relay. If battery voltage is indicated, connect a third jumper wire to Terminal 2 and ground the jumper wire to a known good ground. Check for voltage at Terminal 5. If battery voltage is not indicated, install a new relay.