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.
1991 Mercury Capri Base, AutomaticFACTORY OEM SERVICE PROCEDURE
Ignition Switch Test
- Locate ignition switch connector under dash. Using a 12-volt test light or voltmeter, ensure voltage is present on Black/Yellow wire when ignition switch is turned to RUN or ON position. This will verify proper operation of ignition switch.
- If there is no voltage on Black/Yellow wire, the problem is either ignition switch or circuit between battery and ignition switch.
Factory Service Tools
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
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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.