I use my car for towing quite a lot and all has been fine with the electrics until now, towed a trailer about a week ago and everything working as it should, went to move one today and none of the electrics are working, tried it on 2 trailers to be sure.

I've checked all the fuses under dash and in the boot area but all seem to be ok.

Any idea what to check next? Need to find a solution asap as need to tow again with it on Friday. 2009(10MY) 3.6 TDV8 Vogue
2004 BMW M3 CSL

If nothings working then i'd start with the earth connection as that is common to each light.

What type of electrics are fitted, OEM, single, twin etc ? Current
2017 Range Rover Sport SVR
2001 Porsche 911 Turbo
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2013 Range Rover Autobiography SDV8
2007 Range Rover Vogue SE TDV8
2002 Range Rover HSE TD6
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Possibly it's the trailer electrics rather than the car as it was working before. But if not then check the plugs as a starter for ten. Open them and check the wires are all good before you tackle the car. There is nothing that can't be fixed with a hammer😜😜
FFRR 4.4 SDV8 Autobiography Santorini Black.
KIA E-Niro 4+
2021 Discovery 5 D300 MHEV commercial

Corrosion of the ground wire/pin in the plug is the most likely cause. 2012 Westminster 4.4 TDV8

Have you checked at the plug with a multimeter ?

If it's a factory fit harness its plug and play on the right side panel in the boot just check the white plug to the car and the black plug to the big white grey box is good onto no6 Range Rover

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