How to Check Your Headlights and Indicators at Home
Save yourself a re-test fee. Here is a simple, foolproof method to check all your vehicle's essential lighting before heading to the garage.
Why Lighting is the Leading Cause of MOT Failures
Nearly 20% of cars fail the MOT because of dead bulbs and faulty lights. It is the number one reason for failure across the UK.
Failing an MOT for a £3 brake light is a massive waste of time and money. You risk re-test fees and a permanent fail mark on your car's history. Check your lights at home. It takes ten minutes.
A Complete Lighting Checklist for Your Vehicle
Park your car, turn the ignition on (engine off), and check these exactly:
- Headlights: Test both dipped and main beam. Both sides must be equally bright and the same color.
- Sidelights and DRLs: Check the smaller parking lights and modern LED strips.
- Indicators and Hazard Lights: Check all four corners and the side repeaters on the wings or mirrors. They must flash at a steady rate.
- Brake Lights: Ensure all illuminate instantly, including the high-level central strip.
- Fog Lights: Test the rear fog light. Front fogs are tested on cars built after March 2018.
- Reversing Lights: Put it in reverse and check the white rear lights.
- Number Plate Lights: The classic trap. Check both tiny bulbs above the rear license plate.
How to Check Your Lights Without a Helper
You don't need a mate to check your brake lights. Use your mirrors.
Reverse close to a garage door, window, or pale wall. Hit the brakes and look for the red reflection. For reversing lights, engage reverse (ignition on, engine off) and look for the white glow. Or, just prop your phone up against a wall, hit record, and test the lot.
Dealing with Fogged or Yellowed Headlight Lenses
Cloudy plastic headlight lenses will fail an MOT because they scatter the beam pattern. Sun damage and road grit ruin the clear coat.
You don't need expensive new headlight units. Buy a restoration kit. A bit of wet-sanding and polishing clears them right up in an hour.
Replacing Blown Bulbs: A Quick DIY Fix
Replacing a standard halogen bulb is an easy driveway job. Check your manual for the exact bulb type (H7, H4, 501) and the access points behind the light cluster.
Never touch the glass of a new halogen bulb with bare fingers. The oils from your skin cause the bulb to overheat and shatter. Use clean gloves or a paper towel.
About Mr Need
Mr Need is a Glasgow-based automotive specialist with over 15 years of experience in vehicle diagnostics, garage servicing, and MOT compliance.
Need an MOT in Glasgow?
Don't risk driving without a valid MOT. Find the highest-rated, most trustworthy testing stations in Glasgow today.
Find a Garage Now