Does any one know this sensor ?

It is located under the battery and connected to the gearbox i think


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Reverse light sensor

Thank you so much for your reply but what is its function ? Is it attached the gearbox ?

If 2 wires, it's the reverse light switch.

It does nothing more than switch the reversing light on when the gearbox is in neutral. Yep, it's worked by the gear selector mechanism in the gearbox itself.

MOT necessity, but "really" isn't a sensor, has no effect on the engine.