Is Your Car MOT Ready? 5 Quick Checks You Can Do Right Now

You've got an MOT coming up. Maybe it's next week, maybe it's tomorrow. Either way, you want to know: is your car going to pass?

Here's the good news. You don't need a ramp, a toolbox, or a mechanical bone in your body to catch the things that fail cars most often. Five checks. Ten minutes. And you'll either walk into that MOT with confidence — or catch something that would've cost you a retest fee and a wasted afternoon.

Let's go through them.

---

1. Walk Around and Check Every Light

This is the big one. Lighting faults cause 24% of all MOT failures — more than any other single category. A blown bulb that you haven't noticed is the most common reason cars fail.

Here's what to do:

1. Turn your ignition on (don't start the engine).
2. Switch on your headlights (dipped beam). Walk to the front. Both working?
3. Switch to main beam. Both working?
4. Turn on your indicators — left first, then right. Check front and rear.
5. Get someone to press the brake pedal while you check the rear. Both brake lights lit up?
6. Check the rear fog light.
7. Check the reversing light (put it in reverse with the ignition on).
8. Finally, check the number plate light at the back. It's a tiny bulb that's easy to forget.

No helper? Park close to a wall or garage door at night. You can see the reflections of brake lights and indicators yourself.

If anything's not working, it's almost certainly a blown bulb. Most car bulbs cost £1–£5 and take minutes to swap. Your car's handbook will show you which type you need and how to access them.

Time: 3 minutes. Potential saving: £30–£50 in retest fees.

---

2. Check Your Tyres

Tyre failures account for 12% of MOT failures, and they're completely avoidable with a quick look.

Tread depth: The legal minimum is 1.6mm across the central three-quarters of the tyre, around the entire circumference. The easiest check? The 20p test. Slot a 20p coin into the main tread grooves. If you can see the outer band of the coin, your tread is getting dangerously low.

Condition: While you're down there, look for:

• Bulges in the sidewall (usually from pothole damage) — instant fail
• Cuts or cracks in the rubber
• Any exposed cord or fabric

Matching: Both tyres on the same axle need to be the same size. You'd be surprised how often someone gets a puncture repaired with whatever the tyre shop had in stock.

Time: 3 minutes. Potential saving: £50+ (retest fee, plus buying tyres somewhere cheaper than the garage).

---

3. Wipers and Washer Fluid

This one takes about 30 seconds and catches a failure that's almost embarrassing to explain.

Wipers: Turn them on. Do they clear the screen properly, or do they leave smears and streaks? Wiper blades perish over time — the rubber hardens, cracks, and stops making proper contact. If they're not clearing well, swap them. A pair of blades costs £6–£15 and clips on in two minutes.

Washer fluid: Squirt your windscreen washers. Does fluid come out? If the bottle is empty, that's an instant MOT failure. Not "advisory" — failure. Pour in a couple of quid's worth of screenwash concentrate mixed with water and you're done.

It sounds ridiculous, but empty washer fluid fails thousands of cars every year.

Time: 1 minute. Potential saving: £25–£50.

---

4. Dashboard Warning Lights

Modern MOTs check dashboard warning lights, and any of the following being illuminated is an automatic failure:

• Engine management light (the little engine symbol)
• ABS warning light
• Airbag warning light
• TPMS light (tyre pressure — on cars registered from January 2012)
• Electronic stability control (ESC) light

Here's how to check: turn the ignition on without starting the engine. You should see all the warning lights illuminate briefly (that's the self-test). Now start the engine. They should all go off within a few seconds.

If any light stays on, get it investigated before the MOT. Don't just hope the tester won't notice — they will, and they have to fail you. There's no discretion on warning lights.

Time: 1 minute. Potential saving: the entire MOT fee (you'd fail anyway).

---

5. Number Plates

7% of MOT failures come down to number plates. This one genuinely catches people off guard.

Check:

• Both plates are there and firmly attached (not dangling or held on with tape)
• Characters are legible — no heavy fading, cracks, or dirt making them hard to read
• Spacing and font are standard — no stylised characters, no illegal spacing
• The number plate light works — the rear plate must be illuminated

If your plates are battered, cracked, or yellowed from sun exposure, replacements cost about £15–£20 for a pair from any registered number plate supplier. You'll need your V5C logbook as proof of entitlement.

And yes, just giving them a good clean can make the difference between a pass and a fail.

Time: 2 minutes. Potential saving: £25–£50.

---

The 10-Minute Verdict

That's it. Five checks, about ten minutes of your time, and you've covered the issues responsible for roughly 58% of all MOT failures in the UK.

Check	% of MOT Failures	Time	Fix Cost
Lights	24%	3 mins	£1–£10
Tyres	12%	3 mins	£2–£60
Wipers & washers	8% (visibility)	1 min	£2–£15
Warning lights	Varies	1 min	Varies
Number plates	7%	2 mins	£0–£20

None of these checks require any mechanical knowledge. None of them require special tools. And the fixes — when fixes are needed — are among the cheapest in motoring.

The average MOT retest costs £25–£50. The average time wasted on a second trip? At least a couple of hours. For ten minutes of checking, that's a pretty good trade.

---

Want to Go Deeper?

If you want to check everything the MOT tester will look at — brakes, suspension, exhaust, steering, the lot — our complete MOT checklist walks you through the full test in order.

And if you want to know what your specific car is likely to fail on, run a free vehicle health check. Enter your reg, and our AI analyses your car's MOT history, known weak spots for your make and model, and tells you exactly what to watch for — in plain English, not mechanic-speak.

It takes 60 seconds. And it might save you a lot more than that.