LR3 with 50,000 miles - New battery - great condition. This has happened three times now driving on a regular flat town road - it will not automatically shift past first gear. I have to stop turn engine off then it seems to work. Today, I drove 5 miles with everything working fine - stopped at a light then it would not shift past first gear it then showed three lights on the dash- the orange BRAKE word, the air suspension light warning, the orange triangle in circle. I turned engine and on again and all error codes disappeared. All brake lights and exterior lights all work correctly. Hooked up a scan tool and the error code that shows up is PO504. Any ideas?

 

Not sure what the code is but the brake switches on these trucks are known to cause weird problems...