Xsara Oil Pressure Warning Light

Interesting. I had a similar issue with my old Vauxhall Astra, although that was a petrol engine. Warning lights flashing, errors stored – sounds familiar! In my case, it turned out to be a dodgy connection to the sensor. The 'error memory' you mention refers to diagnostic trouble codes, or DTCs, stored by the car's computer. Have you tried wiggling the connector while the engine is running (carefully, of course!) to see if it affects the warning light? Also, did you check the condition of the wires themselves? Sometimes the insulation can crack or fray, causing intermittent shorts.

Thanks for the advice! I haven't tried wiggling the connector while the engine is running – I'll give that a go. When you say check the condition of the wires, do you mean looking for any breaks in the wire itself, or just the insulation?

Yes, both! Inspect the entire length of wire you can access. Cracks in the insulation can expose the wire to moisture and cause a short. A break in the wire will obviously interrupt the signal. Given that it's a diesel and the age of the car, it's quite possible that the issue lies with the wiring harness. Ultimately, the diagnostic codes are helpful, but it sounds like you might benefit from taking it to a workshop. They will be able to quickly confirm the fault with specialized tools.

Thanks again for your help! I took it to a local garage, and you were spot on – it was a faulty connection. They replaced the connector, and all the warning lights are gone. Cost me 95€, including labour.