PG9 prohibition and MOT failure investigations. Every gap in the file found.

A PG9 is the one piece of paper every operator dreads. It means an examiner has found a defect bad enough to stop the vehicle being used, either straight away or within a few days. Under DVSA’s guide to maintaining roadworthiness, a delayed prohibition can run for up to 10 days, and the prohibition is not lifted until an examiner is satisfied the vehicle is fit for service. Getting it cleared is the easy part. The harder part is showing why it happened and what you changed.

What an examiner looks at

Each defect on a prohibition can be endorsed. An S means a significant failure of roadworthiness compliance: something that should have been caught at the last safety inspection or the walkaround, or that the driver would have noticed from how the vehicle drove. An X means a random failure that says nothing about the maintenance system, like a bulb that has just gone. No endorsement means the examiner could not tell either way.

In a maintenance investigation, the examiner assesses every roadworthiness prohibition in the sample period, confirms or changes the S or X marking by checking your records, and looks for trends. Where there have been prohibitions in the last 15 months, they check the PG9 files where possible and run a detailed record analysis using the safety inspection period calculator and analysis tool (SIPCAT) to get at the root cause. A trend of prohibitions for safety-critical defects is a reason to report the operator to the Traffic Commissioners.

DVSA’s OCRS guidance also says plainly that operators need to make sure test failures and prohibitions are investigated. So the investigation is expected. What matters is whether yours would stand up.

PG9 records

Every prohibition goes into PSVault as a PG9 record against the vehicle, with the defects and the clearance when it comes. It also counts in your OCRS tracking, so you can see what it has done to the score. For more on the notices themselves, read PG9 prohibitions explained.

The prohibition investigation

Each PG9 gets its own investigation. PSVault links what it already holds:

• the notice itself
• the rectification job from the workshop
• the last full safety inspection on that vehicle
• the clearance
• the driver’s walkaround from that day

It then shows what evidence is missing. If there was no walkaround that day, or the last inspection sheet was never signed off, you find out now rather than when an examiner asks for the file. It also lists the facts about the items concerned, so the history of each one is in front of you.

Follow-up actions get an owner and a due date, the same as actions from a self-check. When the investigation is done, it is signed and printed as a PDF that sits with the PG9 on the vehicle file.

MOT failures and passes after rectification

Test history is its own question in a maintenance investigation. Examiners look at safety-critical failures, multiple failure items, repeated retests and repeated passes after rectification as signs of poor maintenance. An S mark can also follow a defect at annual test that should have been found before the vehicle was presented.

PSVault treats an MOT failure, or a pass after rectification, the same way as a prohibition. The investigation links the pre-MOT inspection and its brake test, the previous three safety inspections, the repair job, the retest and the walkaround. Laid out side by side, it is usually obvious whether the defect was missed, was new, or was spotted and never put right.

SIPCAT analysis

PSVault runs a SIPCAT analysis following DVSA’s spreadsheet, so you can look for the same patterns an examiner would. One of the answers is whether there was a related driver defect report. PSVault fills that in from missed defect tracking: when an inspection, a gate check or a roadside check finds a defect a driver should have spotted, it looks back at the walkarounds since the item was last confirmed sound and records each one that passed it.

How it feeds the self-check

Prohibitions, S marks and test history all feed the maintenance investigation self-check. A prohibition with a signed investigation, a cause and closed actions reads very differently from a PG9 and a repair invoice. It does not make the prohibition go away, and nothing will. It shows you looked at it properly.