The number of MOTs tests carried out in Northern Ireland between January and March fell by nearly half from the same period last year due to lift breakdown issues.
During the first three months of this year the DVA conducted 145,000 vehicle tests, down 49% on the same period last year.
It is the lowest quarterly total on record.
The information came to light after the Department for Infrastructure (DfI) published their quarterly Driver, Vehicle, Operator and Enforcement statistics.
While the Covid-19 shutdown stopped any tests being carried out in the last week of March, the main reason for the dramatic drop was the breakdown of lifts at MOT centres across Northern Ireland.
Cracks were discovered in 52 out of 55 of the existing vehicle lifts and thousands of tests were cancelled as a result.
The defects were caused by “fatigue”, engineers said.
On March 24, in the interest of public safety and to tackle the spread of coronavirus, the DVA suspended all vehicle testing for three months, until June 22.
Drivers with MOTs due during the lockdown have been granted one year exemptions.
New lifts are now ready for installation, but all MOT centres were offered to the NHS for use as Covid-19 testing centres.
The DfI's statistics show that during the 2019-20 financial year the DVA carried out over 999,000 MOT tests, an 8.3% decrease on the previous year's record high.
Excluding January to March, the DVA had carried out 5% more vehicle tests during the first nine months of 2019-20 than in the same period the previous year.
The pass-rate for full tests in 2019-20 was 82.1%, an increase on the 81.8% last year, and the highest pass-rate on record.
The DVLA registered approximately 50,300 new private cars in Northern Ireland during 2019. This is 2.5% lower than the figure recorded for the same period in 2018 and the lowest total since 2012.
The most popular new private-car was Ford (13%), with grey the most popular colour (22%) and petrol the most popular fuel-type (59%).
There were 1,212,000 vehicles licensed in Northern Ireland as of December 31 2019, an increase of 2.3% on last year. The overwhelming majority (83%) were cars.
The number of theory tests conducted during 2019-20 decreased by 3.5% compared to last year, from nearly 72,300 to approximately 69,700.
The pass-rate for private-car theory tests was 46.3%, a small increase of 0.9 percentage points on the record low in 2018-19.
The DVA conducted approximately 55,400 driving tests during 2019-20, a decrease of 4.3% from 2018-19 and the lowest total for five years.
The pass-rate for these tests was 57.9%, down by 0.9 percentage points on last year, but broadly unchanged over the past five years.
Over 240,000 licensing transactions were carried out by the DVA during 2019-20. This represents a decrease of 4.6% in comparison with the volume carried out in 2018-19.
At March 31 2020, there were almost 1,121,000 full and eligible licence holders with private-cars / light vans entitlement. This was a rise of 1.3% compared with the total twelve months ago.
As of March 31, there were approximately 9,600 licensed taxi drivers, down by 6.6% when compared with the same point of 2019.
Similarly, there were nearly 8,600 licensed taxi vehicles, a decrease of 2.1% when compared to March 2019, and nearly 10% lower than March 2014.
During 2019-20, DVA Enforcement staff spot-checked just under 4,500 vehicles, of which 38% were heavy goods vehicles. This was 11% less than last year, and is the lowest annual total since 2012.