Vauxhall Insignia Electrical Gremlins: Terminal 30 Issue?

Hi there! I had a similar issue with my 2016 Vauxhall Astra (I have some experience working on cars, but mostly basic maintenance stuff). My symptoms were almost identical, unusual warning lights, weak starts, and flickering lights. Turned out it was just a failing battery, even though it wasn't that old. Took it to my trusted local workshop, and they diagnosed it properly with their testing equipment. The battery had a few bad cells and wasn't holding charge properly. Had it replaced for about 290€ (including fitting and diagnostic), and all those issues disappeared immediately. Been running perfectly since then. Could definitely be the same issue with your Insignia, but I'd need to know: How old is your current battery? Are these symptoms worse in cold weather? Have you had any other electrical work done recently? Let me know these details and I might be able to help more specifically!

Thanks for sharing your experience! I'm having the exact same symptoms with my Insignia. My current battery is the original one from 2018, and yes, it's definitely worse when it's cold. Haven't had any electrical work done yet, and I'm at 6422 KM since my last service. Really hoping it's just a battery issue like yours was, sounds way less scary than a terminal 30 problem! Did you notice any improvement in starting time after the battery replacement?

Hey again! Yes, absolutely, the starting time improvement was actually one of the first things I noticed after getting the new battery. It was like night and day difference! My Astra now starts up instantly, whereas before it would crank for a few seconds, especially on cold mornings. Given what you're describing about your Insignia, original 2018 battery and symptoms getting worse in cold weather, it's sounding more and more like we had the same issue. Five years is actually a pretty typical lifespan for these factory batteries, especially if you're doing lots of short trips or city driving. I remember being really relieved when it turned out to be just the battery rather than the terminal 30 problem my mechanic initially suspected. The repair was straightforward and sorted everything out in one go. One thing I forgot to mention in my first reply, before changing the battery, I also noticed my stop-start system wasn't working consistently anymore. Did you experience that too? It's another classic sign of a failing battery in these Vauxhalls. If I were you, I'd definitely get the battery tested first before diving into more complex electrical diagnostics. Could save you a lot of time and money!

Thanks so much for all this detailed info! You've actually made my day a bit better, and yes, now that you mention it, my stop-start system has been really inconsistent lately too. I hadn't even connected that to the battery issue! I'll definitely get the battery tested first thing tomorrow morning. You're right, it makes total sense to start with the simplest explanation, especially since our symptoms match up so perfectly. Really hoping for that same "night and day" difference you experienced with your Astra! Thanks again for taking the time to share your experience. It's been super helpful, and I'll update the thread once I get it sorted in case anyone else runs into the same problem!