Nct

If the car is diesel they won’t carry out the emissions test with an engine light on.

Petrol cars are fine

I would caution against removing the battery depending on the car.

Newer cars tend to need a diagnostic tool when installing a battery to reset the Battery Monitoring System, so disconnecting for a few minutes might do more harm than good.

Most cars will have a manual way of resetting warning lights. Have you tried Googleing how to manually reset the error?

my car failed last test because of a brake warning light. New pads and sensors front and back but I couldn't get the front warning indicator to reset. The tester could see the new pads and I explained the indicator wouldn't reset but got no joy from him. Eventually, after trawling the net and trying different approaches, I managed to get it reset from the dash and it was just a visual to get the cert

I'd be surprised if a modern car doesn't have the capability to reset service indicators or other warning lights from the dash. A simple internet search will probably answer the OP's question

fair enough however, since the malfunction has been corrected, there might be a way of clearing it without an OBD scanner eg disconnecting the battery for a while, switching the ignition on a number of times or it may eventually clear itself. An internet search including the make and model of car would probably point in the right direction.

Yeah, but the poster said that most cars have a manual way of resetting warning lights, which isn’t true. I wouldn’t call what you described a ‘manual’ way of doing so.

we don't know what the car is, we don't know what the malfunction is, we don't even know if there's an actual warning light on. The OP only mentions a dashboard notification (which perhaps only comes up briefly when the car is started) that indicates a malfunction which has been corrected

I don't know if such a notification would be a fail for the NCT but I'd want rid of it

A service reminder light won't cause a fail if that's what you are seeing.

If it's a diesel they will refuse to do the emissions test with the the engine management light on which means you can't pass in the current state if it's a diesel. My advise would be to get it fixed or otherwise get the light reset in the minutes before the test.

I have a 2017 vw passat for test. Bloody front assit not working light in dash. Needs re aligning. Got it done 5 months ago at a cost of 300 and its off again. Should this light effect the outcome of the test seeing as all its effecting is the cruise control

Soit will still pass the obd test with this warning light on

It was advisory in 2021 to phase it in think you can fail it from 2022 onwards depending on what comes up