DVSA maintenance investigations explained. Know the answers before they arrive.

A maintenance investigation is DVSA checking whether you have the systems, facilities and arrangements to keep your vehicles roadworthy. An examiner looks at a sample of your vehicles, goes through your records and talks to whoever runs transport. The report that comes out of it can be filed and forgotten, or it can land on a Traffic Commissioner’s desk. Which one depends almost entirely on what is in your files on the day.

The useful part is that DVSA publishes the whole thing. The maintenance investigation guidance sets out every question the examiner asks, what is required and how each answer is assessed. The current edition combines the HGV and PSV versions into one guide and was last updated in May 2023. DVSA’s own Guide to maintaining roadworthiness encourages operators to use it to assess themselves. You can sit down with it today and mark your own homework.

How a visit runs

Where possible the fleet check is unannounced. If the vehicles are out, the examiner may book a short-notice appointment instead, ideally at premises with proper inspection facilities. The examiner picks vehicles of different types and ages, at different points in their inspection and MOT cycle, and inspects them as thoroughly as the facilities allow. The guidance sets a recommended minimum:

Vehicles that are genuinely under repair are not normally inspected. But if a coach looks as though it was last driven in a dangerous state, the examiner can inspect it and prohibit it for defects that were there before the work started.

Then the records. If you have had no prohibitions in the last 15 months, the examiner analyses the last 12 months of records. If you have, they look back 15 months and try to check every file connected to a prohibition, plus a random sample. A file means everything relevant for one vehicle: inspection sheets, brake tests, defect reports, repairs. The analysis uses DVSA’s safety inspection period calculator and analysis tool, SIPCAT, which helps show the trends, strengths and weaknesses in your maintenance system. Minimum file samples are:

If the sample turns up significant problems, the examiner widens it to see whether they are isolated or run through the whole fleet.

The four outcomes

Each question section is marked with one of up to four outcomes. These are what actually decide where the report goes.

The result also feeds your OCRS. On the roadworthiness side, a fleet assessment marked unsatisfactory adds 50 points, and one reported to the commissioner adds 100.

The questions that decide most PSV cases

The full set covers fourteen sections, from whether your legal entity matches Companies House to site security. These are the ones where coach and bus operators most often come unstuck. The wording here is ours; the question set itself is worth reading in full.

Inspection and maintenance records

• 4a, suitable and available. Every safety inspection record needs the operator, date, vehicle, make and model, odometer reading, a list of the items inspected and their condition, defects, the maintenance provider, the inspector’s name, details of repairs and who did them, and a signed roadworthiness declaration. A missing model is a minor omission. No records at all is a report to the commissioner.
• 4b, completed. A full set of records, with the brake test report and any wheel re-torque record behind each one. Every inspection must assess braking performance, and the inspector must record how. A road test is not enough. Clear evidence of falsification goes straight to the commissioner.
• 4c, intervals. Inspections at the interval on your licence, with first-use inspections for hired or borrowed vehicles. An occasional slip into the next ISO week is mostly satisfactory. Defects that show the interval is too long are not.
• 4d, forward planning. Inspections, annual tests and calibrations planned at least six months ahead.
• 4e, VOR. Off road records with dates and reasons, checked against tachograph or telematics data. Running a vehicle marked VOR with a safety-critical defect, or using false VOR entries to hide use, is a report to the commissioner.
• 4f, recalls. A system that checks for safety recalls regularly and records the fix on the vehicle file.
• 4g, PSV112. PSV operators must report safety-related incidents to DVSA on the PSV112 form, such as brake failure, wheel loss, fire or a bridge strike.

Driver defect reporting

Question 5a asks whether walkaround checks are effective, and the test is blunt: do your inspection sheets keep finding things a driver should have reported, with no defect report to match? Occasional cases are mostly satisfactory. A regular pattern, or prohibitions the driver should have prevented, is unsatisfactory. Clear evidence that checks are not done, or that records are falsified, goes to the commissioner. Nil defect reports are described as good practice because they prove the check happened. Question 5c asks whether reported defects were assessed and repaired. Defect reports, with the repair details, must be kept for at least 15 months. More on this in our walkaround checks guide.

Facilities, contracts and test history

If someone else does your inspections, there must be a written contract covering the vehicles, the interval and the work, and the contractor named on your licence record must match. You stay responsible for their work, so the examiner expects to see you checking it. Question 6c compares your MOT final fail rate with the national average, after taking out pass with rectification results.

Wheels and tyres

Section 8 wants a wheel security system covering daily monitoring and correct fitting and torque procedures, and a tyre management system that tracks age, pressures and tread depth measured with a calibrated gauge. Deliberately altered or removed date codes are a report to the commissioner. Our guide to tyre age rules covers the ten year limit.

PSVAR, prohibitions and the transport manager

Section 9 checks that vehicles used on local or scheduled services carrying more than 22 passengers meet the accessibility regulations, that accessibility equipment is maintained, and that drivers are trained in disability awareness. Section 10 reviews roadworthiness prohibitions from the most recent of: the last inquiry that looked at roadworthiness, the last fleet check, or the last three years. The examiner confirms or changes the S or X endorsement against your records, and any prohibition showing a significant failing in your maintenance system is reported. Section 12 looks back up to five years for problems you were told about before and have not fixed. Section 13 asks whether the transport manager has effective, continuous control and keeps up CPD.

After the visit

If anything is unsatisfactory or reportable, you get a request for explanation. The response should reach DVSA within 14 days of the report being given to you, with a further seven days allowed only in exceptional cases. Evidence beats promises: a signed maintenance contract, the missing inspection record, a training certificate. Where a fix takes longer, a firm assurance can be accepted, for example committing to a laden roller brake test at every inspection. Be aware that a good response does not undo a report to the commissioner. That recommendation stands either way.

If the report does reach the commissioner, our guide on avoiding a public inquiry explains what happens next.

How to prepare

You cannot prepare the night before. You can make sure the files would pass on any day of the year. A sensible routine:

• Pull three vehicle files at random each month and read them as an examiner would. Is every sheet complete, signed and backed by a brake test?
• Compare inspection defects with driver reports for the same vehicles. Every tyre, light or body defect found in the workshop that no driver reported is a 5a problem.
• Check the forward planner runs at least six months ahead and that no inspection has slipped past its ISO week without a VOR record.
• Make sure the maintenance contract is signed, current and matches your licence record.
• Write up every prohibition: the defect, the root cause and the change you made.
• Check the transport manager’s CPD certificates are on file.
• If your records are electronic, confirm you can print any record on request, that nothing can be altered without trace, and that the data is backed up.

PSVault’s maintenance investigation self-check runs DVSA’s question set against your own records, shows what would be marked down and why, and tracks the actions you take. Its safety inspection sheets are checked the way an examiner would before they can be signed.