Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Visual Inspection
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 .
Once familiar with system being diagnosed, check operation of the following:
- With ignition switch in LOCK position, gearshift lever should be locked in "P" position.
- With gearshift lever in "P" position, ignition switch should be allowed movement from LOCK position to any desired position and back to LOCK position. Ignition key should be removable while in LOCK position.
- With ignition switch in ON position, gearshift lever should be allowed movement from "P" position. Models equipped with BTSI solenoid require that brake pedal be depressed for this operation.
- With ignition switch in ON position and gearshift lever in any position other than "P" position, ignition key is non-removable. Ignition key is removable only when gearshift lever is moved to "P" position.
If shift interlock system operates as specified, system is functioning properly at this time. If system does not operate as specified, inspect mechanical functions of the following:
- Ignition Switch
- Gearshift Lever Assembly
- External Shift Cable/Linkage
- Internal Transaxle/Transmission Shift Linkage
If switch or cable adjustment problems are found, adjust as necessary. See ADJUSTMENTS . If mechanical functions are okay, see the following appropriate test in SYMPTOM TESTS:
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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.
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