Gwilbo25

Hi. I have recently bought a Primastar van, its a 2022 model in the new shape, 2.0L automatic and has only done 3500 miles. The stop / start feature just stopped working yesterday. Before you ask, I am aware of cold engine, having the air con on, plugging in things that use the power etc and have disconnected and turned off everything and it still hasnt started working again. Had the battery checked and its Good, healthy and at its health came out as 89% and charging at 100%. I do both short driving around town and long drives for 2 hours on the motor way and it still doesnt activate. When i do stop, the little green A appears on the dash but with a diagonal line through it, as if to say the stop / start is not available or wont be coming on, then dissappears as normal when i pull off again. No warning lights on dash at all. Its booked in to Nissan garage in 10 days time but they want £130 diagnostic fee, then obviously if its a faulty then it should be covered by warranty. I'm just wondering is there anything i could try myself first? Thanks