Partner Oil Temperature Warning Light

That does sound like a faulty sensor, specifically with what you're describing as a possible issue with the cables. The engine oil temperature sensor, also known as the oil gauge or oil sensor, sends a signal to the ECU (engine control unit) which then decides when to show a warning in the dashboard. If the wire to the sensor is broken or has a bad connection, the ECU might receive an incorrect signal, or no signal at all, triggering the warning light. Have you checked the sensor's connector for any corrosion or loose pins? Also, where exactly did you find the error memory? Did you read it out yourself using an OBD2 scanner?

Yeah, I visually inspected the connector – didn't spot any obvious corrosion. But hard to really see inside those things, right? I used a generic OBD2 scanner to check the error memory.

Right, those connectors can be tricky. If it's not visibly corroded, the issue might still be with a damaged wire within the insulation, or the sensor itself could be failing intermittently. Given the oil pressure light flickering too, which could mean a low pressure situation in your engine with potentially catastrophic consequences, it's definitely worth getting it checked out professionally. At this point, I'd suggest taking it to a workshop to confirm if it's either the temperature sensor (including cabling) or the oil pump.

Thanks for the insights. Took it to the shop. Turns out it was indeed the oil temperature sensor connector. They replaced it and cleared the error. Cost me 95€. All good now.