13 of 14 people found the following review helpful.

Genius5 Review

My 4yr old Audi A5 diesel stop/start feature stopped working in August last year. I checked the resting battery voltage & it was barely above 12V. Having just driven from Liverpool to Surrey that told me the battery was probably struggling a bit (alternator output was 14.6V so that was ok). A friend recommended I try a charger/desulfator and I found the Noco Genius5 and thought I'd take a punt. Initially I tried it with a totally dead 40AH car battery I had in the shed that would not hold a charge. Nearly 6 months on, that's still going strong as part of my solar lighting backup.
I then tried it with my car battery. It took 5hrs to fully charge, then Ileft it overnight in Repair mode. This thing is an 80AH AGM beast so a new one would've cost a fortune. The resting voltage improved to 12.6V and within a few miles of driving, the stop/start feature re-enabled and has been working ever since.
I will probably use this charger in desulfation (repair) mode once a year as a preventative measure.

Yes, I recommend this product.