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.
Car Access System 4
The Car Access System 4 is installed on the right, above the steering column. It assumes the master function for the central locking system. The Car Access System 4 has the exclusive system authorization and is simply supported by the other control units.
The Car Access System 4 also registers the status of the center lock button. The Car Access System 4 activates central locking, depending on the status of the central locking system. Briefly pressing the center lock button triggers the vehicle to lock or unlock.
The Car Access System evaluates the status of the interior trunk button on the A-pillar and the central locking button on the trunk.
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.
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