Koleos weak start flickering lights

I had similar issues a while back. Weak starts and flickering lights usually point to low voltage. It could be the battery sensor messing with the battery charge. Have you checked the battery health with a vehicle diagnostics tool? That might give you a better idea if it's the sensor or the battery itself.

Thanks for the quick reply! I don't have a diagnostics tool. Is there a way to check the sensor without one? Like, is there a specific voltage I should be looking for, or any other telltale signs that the sensor is definitely defective?

Without a diagnostics tool, it's tough to pinpoint it 100%. If you're seeing those symptoms consistently, especially with a relatively new battery, it really does sound like the battery sensor is the culprit. Honestly, to avoid potential damage to other components due to the low voltage, your best bet is probably taking it to a workshop. They can test the sensor properly.

Thanks a bunch for your help! I took your advice and brought it to a workshop. Turns out you were right – it was the battery sensor! The repair cost 315€. All sorted now!