118d overheating

[Gad-Westy]

Just had a text from my mum. She's on holiday in France and her 118d overheated in heavy traffic earlier today. Apparently Amber and then red coolant light came on before she could stop. She let it cool down and then got on her way. Sounds like it was ok after that. She's going to check coolant level in the morning though am I right in saying that the car would probably warn her if it was low? Any common problems on this engine? My first guess is failing waterpump but bit hard to diagnose from here. Worst case i think she has BMW assist coverage for Europe.