How to Know If Your Car Is Ready for Its MOT

How to Know If Your Car Is Ready for Its MOT

An MOT failure is almost always avoidable. The majority of cars that come back with an advisory or an outright fail have something wrong that the driver could have spotted the week before — a blown bulb, a worn wiper blade, a tyre that's crept below the legal limit. Catching these things yourself costs very little. Ignoring them can mean a retest fee, more time without your car, and occasionally a repair bill that's much bigger than it needed to be.

Here's a practical walk-around you can do at home before you bring your car in for its MOT. It takes about 20–30 minutes and doesn't require any specialist knowledge.

---

Step 1: Check All Your Lights

Get someone to help if you can, or park close to a reflective surface. Work through every light on the car:

• ▸Headlights (dipped and full beam)
• ▸Rear lights and brake lights
• ▸Indicators front and rear
• ▸Hazard lights
• ▸Reversing light
• ▸Number plate light
• ▸Fog lights (front and rear, where fitted)

A single blown bulb is an immediate MOT failure. Replacements from a motor factor or a garage like ours typically cost a few pounds for standard halogen bulbs. LED or complex assemblies can cost more, but the point is you want to know about it before the test, not during.

---

Step 2: Walk Around Your Tyres

The legal minimum tread depth is 1.6mm across the central three-quarters of the tyre. A 20p coin is a useful rough check — if the outer band of the coin disappears when you insert it into the tread groove, you're above 1.6mm. If you can see the full outer band, you're likely borderline or below.

Beyond depth, look at:

• ▸Sidewall condition — cuts, bulges, or cracking are automatic failures
• ▸Tyre pressure — a flat or noticeably soft tyre can cause handling issues the tester will pick up
• ▸Spare tyre — not tested directly, but worth keeping road-legal

Typically, budget tyres for a standard family car start from around £50–£70 fitted; mid-range from £80 upwards. It's worth replacing a borderline tyre before the test rather than gambling on it passing.

---

Step 3: Test Your Brakes

You don't need specialist equipment here. Find a quiet, safe road and do a firm (not emergency) stop from around 30mph. The car should pull up straight without pulling to one side. Any juddering through the pedal, grinding noise, or spongy feel is worth flagging — these are things an MOT tester will absolutely notice on the rolling road.

Handbrake function is also tested. On a gentle slope, check it holds the car securely.

---

Step 4: Check Windscreen Wipers and Washers

Run your wipers on a wet screen and check they clear cleanly without smearing or skipping. A blade that streaks badly is a failure. Replacement blades are inexpensive — most can be fitted in minutes.

Washers must also work. Top up the reservoir if it's empty and make sure the jets are aimed at the screen rather than the sky.

---

Step 5: Inspect the Windscreen

A chip or crack in the driver's line of sight — the swept area directly in front of the driver — is a failure if it's larger than 10mm. A chip elsewhere on the windscreen is a failure if it exceeds 40mm. Small chips are often repairable rather than requiring a full windscreen replacement, so it's worth sorting before the test.

---

Step 6: Check Fluid Levels

While fluid levels aren't directly tested in every category, running low on brake fluid or having a warning light on the dashboard absolutely will affect the result. Before your MOT, check:

• ▸Engine oil
• ▸Coolant (when the engine is cold)
• ▸Brake fluid
• ▸Screen wash

If any warning lights are illuminated — engine management, ABS, airbag, or anything else — these will be picked up on the test. An active warning light is a failure. If you're unsure what a light means, a diagnostic scan at a garage will tell you.

---

Step 7: Listen and Feel on a Short Drive

Before you book in, take the car for a 10-minute run and pay attention. Any knocking over bumps, vibration through the steering at speed, unusual noises from the exhaust, or pulling to one side under braking are all worth mentioning when you drop the car off. These aren't things you're expected to diagnose yourself — but noting them means the garage can look more closely at the right areas.

---

Step 8: Check Your Number Plates

They must be secure, clean, and legible. Cracked plates, missing characters, or non-standard fonts are failures. It's a simple thing to check but easy to overlook.

---

What Happens If Something Needs Sorting First?

If you spot something during your check, it's worth getting it looked at before the test rather than hoping it passes. Many garages — including John Downes Garage in Brierley Hill — will identify and repair issues ahead of an MOT booking, meaning you're less likely to face a retest fee or return visit.

---

If your MOT is coming up and you want it done properly by people who've been doing this since 1973, give John Downes Garage a call on 01384 78504 or get in touch through the website. We're a DVSA-approved testing station right here in Brierley Hill, and we'll be straight with you about what your car needs.