The 48-hour walkout by the Public & Commercial Services Union (PCS) is over the imposition of new tests by their employer, the Driver & Vehicle Standards Agency (DVSA) and its refusal to talk about fair working times.
Examiners say that new tests will force them to work longer hours for no extra pay.
The union is also concerned about the safety of the new tests, giving as an example a manoeuvre that requires examinees to move across oncoming traffic to park on the opposite side of the road.
DVSA was forced to clear its schedules for 10,000 tests after more than 1,000 examiners went out on strike, PCS said.
The union blamed both the agency and the Department for Transport for imposing changes to terms and conditions despite being rejected by the vast majority of staff in recent ballots.
It also welcomed Labour’s letter sent to Transport Secretary Chris Grayling urging him to resolve the dispute through talks with the unions.
PCS general secretary Mark Serwotka said: “Ministers need to listen to the concerns of DVSA staff, who have shown that they won’t be bullied and intimidated by tactics of misinformation.
“Now is the time for Chris Grayling to get a grip of this dispute and insist that DVSA management acts in the interests of both learner drivers and its own staff.”