NOTE: Diagnosis of shift interlock system should begin with a general visual inspection. Each model is similar in function, but may be equipped with a variety of components depending upon application. Before beginning any diagnosis, refer to appropriate wiring diagram to become familiar with the system and for use as a guide to pinpoint areas of concern. See WIRING DIAGRAMS .

Inspect mechanical operation of ignition switch, gear selector assembly, shift cable/linkage and internal transmission linkage. Adjust or repair as necessary. See ADJUSTMENTS . If no mechanical problems are found, inspect all electrical components while referring to appropriate wiring diagram as a guide. Ensure all system electrical harness connections are tight and free of corrosion. Check for misrouted wires and damaged components. Ensure system fuses are good and appropriate circuits are properly grounded. Repair as necessary. Once system passes visual inspection, check system operation. See SYSTEM OPERATION CHECK .

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

Visual Inspection

Use the Manual With the Right Hardware

When to See a Mechanic

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