Ford Mondeo mk4 1.8tdci titanium. My battery went flat (car left unused in freezing temperatures). I got a recharge and a jump start and the car is working fine, BUT the stereo radio sat Nav (blaupunkt Travelpilot FX) is not turning on (blank screen / no lights behind buttons). Is there some kind of reboot / hard reset to switch it on?
Those units don't have the best reputation for long term reliability, other than you doing a search online for "known issues" with this unit I've attached a grab of a post that details one of the known issues which happens to sound a lot like your issue.
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