Re:How do I reset the yellow engine light?

There are two sensors, pre and post cat, so if it is picking out the pre sensor I would change that after inspecting the wiring is not damaged or even disconnected!

mickt wrote: Max Headroom What made you decide it was a particular sensor that was causing the battery to go flat as I would have thought that once the ignition was off the sensors are OFF?. Or did you get the car ECU read and it gave it the thumbs down or did you just picked that sensor. Even then I doubt that it would cause a battery problem.
Pony your best bet is to get the charging system checked properly and as mentioned get the codes read. Any decent garage will normally read the codes for you as long as it is not a Dealers!

Hmmm
I think you misunderstood me - The engine management light kept coming on and I disconnected the battery for a few mins and reconn'd it - this re-set the light.
I never mentioned I had a battery problem.

The eng management light has stayed off for some time since replacing that sensor, but has in recent weeks reappeared. Also the guys struggled getting it through its emissions at the MOT so I guess I'm now looking down the barrel of a new CAT.
"There's always bloody something"

Some car cats respond well to a pressure wash, off the car obviously and in both directions. Worth a try.

Interesting one that, Mick! Thanks, I might have to give that a go!