My 2008 range rover sport got pretty wet inside by flash rain through open sunroof, while unattended. The key fob doesn't work now and after manualing shutting off ignition and locking door, my wipers
(cont) randomly go off, as well as inside lights and computer screen. Is there a
switch that shuts everything down until I can take in to mechanic ?
No there is not, open the fuse box and remove just the fuses on the systems that are having problems, do not disconnect the battery as this can cause programming problems with the body computer, then I would put a battery tender on it and then put a small heater inside and just crack the Windows a bit and try to get it all dried out as much as possible, and then see what systems do after they are dry. Note: this could get very expensive very quickly, or you could get very lucky and everything will straighten itself out after it dries.
Pull carpet and make sure whereever your computer is that it is not soaked with water or getting condensation on it from the excess water in cabin.
May not be a bad idea to contact a local shop and let them take care of it for you. Because of the electronics/electrics.
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