Changing the oil is the very thing likely to set it off. Happened to me just a few days ago from an oil change.
I never even had any codes. They are a fussy little thing. Last one only lasted 20 000km, and this is the third one I put in in just a few years.
Good clue is if it goes away when you rev the motor. Drives you batty alright, popping up every time the motor drops back to a low idle, beeping and carrying on.
I wasted a good bit of oil trying to 'service it soon' the first time it happened, ha ha. Before I came here and learned from the others.
Just now I pulled out the sump unnecessarily cause I couldn't imagine it would fail again so soon. Faulty one still looks brand new.
Thought the pickup got blocked twice in a row. Took me hours.
There is a lot of stuff on here about it somewhere. Can't guarantee anything, but it is most likely in my opinion. Once bitten, twice shy, as they say.
Your son needs a 27mm socket to change it long enough to go over the electric plug, and a shortish extension to allow access for the wrench behind the power steering lines. I am going down to mess with the car in a bit, and I will put a pic here later.
