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.
Automatic locking when driving
Whether the function for automatic locking is activated or not at delivery depends on the market. If the function is activated then the side doors are locked when the speed exceeds 7 km/h (5 mph). This is on condition that all side doors are closed, the engine is running and the vehicle is moving forwards. The exception is the tailgate/trunk lid which may be open. The rear electronic module (REM) receives information on whether or not the engine is running from the engine control module (ECM).
The indication that the engine is driving the vehicle forward differs between vehicles with automatic or manual transmission. On vehicles with automatic transmission the position of the gear selector is obtained from the transmission control module (TCM). The gear selector must not be in Park (P) or Neutral (N) position for the automatic locking to work. On vehicles with manual transmission the rear electronic module (REM) receives information on the speed of the vehicle from the brake control module (BCM). At the same time the accelerator pedal must be partially actuated for the locking to be performed.
The door can be unlocked again with a normal unlocking procedure
An unlocking procedure activates the function. Example: the vehicle is unlocked, started and driven off. When the vehicle exceeds 7 km/h (5 mph) the side doors not already locked will be locked. If the vehicle then stops and the side doors are unlocked for a passenger to get out, e. g. with one of the central locking switches, then the vehicle will not be automatically locked the next time the vehicle exceeds 7 km/h (5 mph). However, if the passenger getting out opens the door by pulling in the inner door handle or unlocks the door using the lock button then the door will be locked when the vehicle next exceeds 7 km/h (5 mph).
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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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