Peugeot 307 Oil Temperature Warning Light

The symptoms you describe certainly point towards a potential issue with the oil temperature sensor or its associated circuitry. Given that you've observed both the oil temperature and pressure warning lights, it's prudent to investigate further. Have you noticed any correlation between engine temperature and the occurrence of the warning lights? Does it happen more frequently when the engine is cold or after it has reached operating temperature?

That's a good point! I think it happens more when the engine is warm, especially after driving for a while. Does that change your diagnosis? Like, could it still be the sensor even if it only acts up when warm?

The fact that the issue predominantly manifests when the engine is warm strengthens the likelihood of a faulty oil temperature sensor or a degradation of its wiring due to heat exposure. Considering the age of the vehicle, it is plausible that the cable or plug connection of the component is defective. While a further inspection of the wiring harness is advisable, I recommend consulting a qualified technician to confirm the diagnosis and replace the sensor. Ignoring the issue may lead to consequential damage. The cost of repair is around 95€.

Thanks! I appreciate the help. Took it to a mechanic, and you were spot on – it was indeed the oil temperature sensor and a corroded connector. New sensor and some connector cleaning, and the problem is gone! Thanks again for steering me in the right direction.