CAUTION: If battery terminals are disconnected while engine is running or when ignition switch is in "ON" position, malfunction of computer or damage to semi-conductors could result.

Turn ignition switch to "OFF" position. Remove harness connectors "A" and "B" from ECU. See Fig 1 .
Set check switch of Feedback Carburetor Checker (09341 21000) to "OFF" position.
Set select switch of checker to "A" position. Connect FBC Wiring Harness Connector (09391-21101) to connectors of FBC checker.
Connect FBC connector to ECU connectors. Perform checks according to FBC SYSTEMS CHECK PROCEDURE CHART. See Fig 2 .
If checker shows variation from specifications, check for defective sensor and electrical wiring. Repair or replace defective components.
After repair or replacement of defective components, recheck system with checker. Set check switch of checker to "OFF" position.
Set ignition switch to "OFF" position. Disconnect all harness connectors and reinstall in proper harness connectors.

Fig 1: Electronic Control Unit Connectors

When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

• You smell fuel, burning insulation, or see smoke.

• Brakes feel soft, pull hard to one side, or make grinding noises.

• The engine overheats, stalls repeatedly, or misfires under load.

• You are missing required tools, torque specs, or safe lifting equipment.

• You are not confident in the next step or safety outcome.

Safety Warning

Diagnostic Circuit Check

Use the Manual With the Right Hardware

When to See a Mechanic

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