DSA informs DVLA of illegal plates on cars for driving test
Having illegal number plates on a car presented for the driving test will not cause the DSA examiner to terminate the test, but the details of the car and the pupil will be passed onto the DVLA.
Illegal number plates are those that do not conform to the DVLA standard, and are usually cherished private number plates that have been made to look like the car owners name or a popular word.
Also note that the police can stop a driver at anytime if the number plates are illegal or there is anything about the car that does not conform to the road traffic act.
Make sure your car is road worthy and not carrying illegal number plates when presenting yourself for the driving test.
Own car on driving test