Had a similar thing happen to me a month or so ago. Drove down to the local Bunnings, all OK. Got back in the car, RNS dead - no radio, no OPS, nothing. Tried turning the ignition off and back on again; still no action.
Couldn't have been heat related, as was an underground carpark, and a coolish day.
Anyway, drove 10 minutes up the road; ducked into another store for about 10 minutes; start the car, and all back to normal. Haven't had a problem since.
Ain't technology wonderful!
MY17 Passat Alltrack Wolfsburg, Indium Grey, Sunroof
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