Computers and Control Systems: Service Precautions

ELECTRONIC CONTROL SYSTEM PRECAUTIONS

1. Before removing Multiport Fuel Injection (MFI) / Sequential Fuel Injection (SFI) wiring connectors, terminals, etc., first disconnect the power by either turning the ignition switch OFF or disconnecting the battery terminals.

NOTE: Always check the diagnostic trouble code before disconnecting the negative (-) terminal cable from the battery.

2. When installing the battery, be especially careful not to incorrectly connect the positive (+) and negative (-) cables.
3. Do not permit parts to receive a severe impact during removal or installation. Handle all MFI/SFI parts carefully, especially the Engine Control Module (ECM).
4. Do not be careless during troubleshooting as there are numerous transistor circuits and even slight terminal contact can further troubles.
5. Do not open the ECM cover.
6. When inspecting during rainy weather, take care to prevent entry of water. Also, when washing the engine compartment. prevent water from getting on the MFI / SFI parts and wiring connectors.
7. Parts should be replaced as an assembly.
8. Care is required when pulling out and inserting wiring connectors.
- Release the lock and pull out the connector.
Do not pull on the wires.



- Fully insert the connector and check that it is locked.

9. When inspecting a connector with a volt/ohmmeter.



- Carefully take out the water-proofing rubber if it is a water-proof type connector.



- Insert the test probe into the connector from wiring side when checking the continuity, amperage or voltage.
- Do not apply unnecessary force to the terminal.
- After checking, install the water-proofing rubber on the connector securely.




10. Use SST for inspection or test of the injector or its wiring connector. (SST 09842-30070)