Twingo Undervoltage Issue

Sounds familiar. I had similar gremlins in my Twingo. The symptoms you describe – weak starts, system failures, flickering lights – all point to a potential voltage drop. Have you checked the battery voltage when the engine is running? It should be around 14V. If it's significantly lower, say around 12V or less, the alternator might not be charging the battery properly. This could be due to a faulty alternator, a bad voltage regulator, or even a parasitic draw somewhere in the electrical system. Think of it like a leaky bucket – the alternator is trying to fill it (the battery), but something is draining it faster than it can fill.

Good analogy! I haven't put a multimeter on it while it's running, I'll check that first thing tomorrow. When you say parasitic draw, what sort of things should I be looking for? Is there anything specific to the Twingo that tends to cause this kind of drain?

Parasitic draw can be tricky. It's like finding a tiny hole in that bucket. Common culprits are things like aftermarket accessories (alarms, stereos), a glove box light that stays on, or a faulty door switch. In the Twingo, I've heard of issues with the central locking module causing a drain. However, given the severity of your symptoms and the fact that multiple systems are failing, I'd lean towards a charging system problem first. Testing the alternator output is the key. In my case, after chasing phantom drains, it turned out to be a dying alternator, so I would recommend going to the workshop and asking for a professional diagnostic. It will save you time and nerves.

Thanks for the advice! I checked the voltage, and you were spot on – the alternator wasn't putting out enough juice. Took it to my local mechanic, and they confirmed the alternator was toast. New alternator and battery later, and everything's back to normal. Total cost was 290€.