I had my low coolant alarm sound on startup and found a dropped level in the expansion tank. I topped up and suspected a failed expansion cap so I changed it.
Shortly afterwards the low alarm went off again. Switched off.
Checked the level and I could see it dropping as I watched it.
Checking the car, I could see wisps of steam from the radiator area and coolant dripping from the offside.
Whipped the slam panel off and saw this.
Can you see the problem?
No, how about now?
That'll be a new radiator required then. So relieved this happened on my drive, not on the motorway at 70mph.