Nissan Caravan Coolant Loss

Low coolant on a diesel can be a few things. Have you checked the radiator hoses for any obvious leaks? Also, keep an eye on the coolant reservoir itself. Any signs of a head gasket issue, like milky residue under the oil cap?

Thanks for the quick reply! I did a quick check of the radiator hoses and didn't see anything obvious, but I'll take a closer look. Where exactly should I be looking for this 'milky residue' you mentioned?

The milky residue would be on the underside of the oil filler cap or on the dipstick. If you aren't seeing that, then the leak is most likely external. Given that it's throwing a code, I'd recommend getting it pressure tested to properly find where the coolant leak is coming from.

Appreciate the advice. Took it to a local shop, and turns out there was a tiny pinhole leak in one of the lower radiator hoses, almost invisible. They replaced the hose and refilled the radiator fluid. Repair cost was 52€. All good now, thanks again!