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You should find the TV unit and radio tuner under the carpet in the spare wheel well of your cars boot. When it comes to swapping out the units you need to ensure your sat nav system is fully shut down prior to disconnecting anything (or even the cars battery) to prevent damaging any of the hardware. To do this, follow these instructions:- Open any doors plus boot/bonnet if you need access to these areas. Watch the little red LED (Light Emitting Diode)
on the nav computer (which is located in the side of the boot space) until it extinguishes. Do not open or close any doors or press any keyfob or central lock buttons else you'll "wake" up the satnav again. Whilst the LED
is extinguished the satnav system is shut down and it is safe to remove components or disconnect the cars main battery.