The Most Common Reasons Cars Fail France's Roadworthiness Test (and What Repairs Cost)

Every year, around 18.94% of vehicles tested at France’s contrôle technique — the French equivalent of the UK’s MOT — have to come back for a retest [official national rate, see our 2025 barometer]. But not all fault categories carry the same weight — and, more importantly, they don’t all cost the same to put right. Here’s the real national breakdown, category by category, and what each type of repair costs.

The breakdown by fault category

Six categories cover every reason for a retest in France. Here’s their national weight, from most to least frequent:

Category	National weight
Visibility and other minor categories	25%
Suspension	24%
Braking	20%
Lighting & electrics	20%
Emissions & engine	8%
Steering	3%

Two things worth knowing to read this table correctly:

• “Visibility and other minor categories” is the single most frequent category, but it’s a composite bucket (wipers, mirrors, windscreen, warning lights and other ancillary checks) — unlike the other five categories, it doesn’t break down into individually priced repairs: it typically corresponds to a simple adjustment or wear-part replacement, billed at around €60 on average.
• Emissions & engine only accounts for 8% nationally, but that figure hides a binary reality: every intervention within it applies exclusively to combustion-engined vehicles (petrol/diesel). For an electric vehicle, this retest category simply doesn’t exist.

What each type of repair costs

For each mechanical category, a price range (parts + labour, independent garage, supermini segment used as the example):

• Braking: front brake pads €90-150, front discs + pads €240-380, rear pads + discs €210-330, brake fluid flush €50-80.
• Suspension: front shock absorbers (pair) €200-320, ball joints/wishbones €150-280, wheel bearing €150-250, wheel alignment €60-90.
• Steering: ball joints/wishbones €150-280, wheel alignment/geometry €60-90 — the two interventions that make up this category, the rarest of the six (3%).
• Emissions & engine (combustion-engined vehicles only): EGR valve €250-450, DPF replacement €600-1,000, catalytic converter €400-700, spark plugs (petrol) €80-150, injectors x4 (diesel) €800-1,200, exhaust/rear silencer €150-280.
• Lighting & electrics: 12V battery €100-160, alternator €300-500, electronic diagnostics €40-70.

Detailed pricing by segment and model is available on each model page (in French), or in the budget simulator (in French) for a personalised estimate.

How to reduce your risk of a retest

One simple thing worth checking before presenting a car for testing: the categories that most frequently cause failure (see above) are also the ones a quick visual check will often catch in advance — tyre and brake pad condition, all lights working, wipers and mirrors in good order, no warning light left on the dashboard.

Source data: UTAC-OTC (France’s roadworthiness test authority) for the category breakdown, automotive maintenance cost survey for the price ranges. Full methodology on the methodology page (in French).