The Ministry of Transport (MoT) is an annual test of roadworthiness and emissions required on most vehicles over three years old.

The test for Class 4 vehicles, which includes ‘motor caravans’, costs £54.85 officially – but you’ll often find testing stations offering it for less, so shop around.

You’ll also need to make sure the garage can accept your motorhome, because they vary in what type of vehicle they can legally test.

Do some pre-test checks!

Before you head off to the test centre, there’s plenty you can do to boost the chances of your ’van passing, first time.

Take a test drive, noting how your motorhome handles.

Does the steering pull to one side, especially when braking? Are there noises when the steering is on full lock?

Is there knocking when on rough roads? Does it lean to one side?

A grinding noise when braking announces that the front disc pads have worn.

Don’t forget to check the tyre pressures and tread depth, and ensure all of the fluids are topped up and that the wipers still do a good job.

Click through the carousel of photos at the top of this page, for more on pre-MoT checks.

What’s tested?

All exterior lights, including front and rear fogs, end and outline lights are checked for operation, and the headlamp aim is assessed (dipped beam should be at least 0.5% below horizontal).

You can check this for yourself by pointing the ’van towards a wall or garage door after dark.

Stop lamps, hazard and direction indicators, reflectors, the horn and all visible electrical wiring are also checked.

A broken lens can mean a fail if anything other than a red light is shown to the rear.

It is my understanding that additional lamps (not original equipment) will not be inspected, but the latest fashion of coloured lights and bulb masking will fail.

Damaged, distorted or cracked wheel rims and insecure wheel studs or bolts will receive a fail certificate, as will tyres of different sizes, or a combination of crossply/bias-belted/radial on the same axle. Don’t forget that many tyre companies now offer mobile replacement.

Tyre pressure-monitoring systems (TPMS), which are fitted to many new motorhomes registered from January 2012 onwards, are now a test item, so make sure yours is functioning properly.

Get underneath

The MoT test also includes a good look at the motorhome’s underside.

The steering, suspension, steering rack, front suspension, springs, bearings and driveshafts are tested, along with the torsion bars, suspension arms, rear suspension and bearings, shock absorbers and more.

The tester will exert reasonable pressure on the steering wheel to check for excessive movement.

Power steering (hydraulic or electrical) should be tested with the engine running and wheels on the ground, to assess the amount of free play in the steering wheel.

You can check for damaged or split steering rack rubber gaiters, as well as leakage, before the test, but make sure the vehicle is properly supported on axle stands before you climb beneath it!

Still underneath, some contention has arisen with vehicles being failed for inadequate clearance between the rear axle and bump stop.

Manufacturers state that the bump stop now becomes part of the suspension, and is not a sign of weak or overloaded axles.

As for shock absorbers, owners can visually inspect for leakage or defective fixings.

Excessive leakage will fail because the shock won’t be performing correctly and could destabilise during cornering.

Front shock absorbers are generally now part of the front suspension leg, called a MacPherson strut.

Again, look for leakage or broken coil springs, a broken leaf on multi-leaf rear suspension and worn end shackle bushes.

Stopping power

Don’t forget the brake pipes, cables and hoses, servo assist and master cylinder.

The main test inspection takes place while the ’van is on the ramp, and the brake efficiency test is carried out on the brake test machine (usually part of a rolling road).

Newer motorhomes will have had a catalytic converter fitted from new, and the vehicle must have one to pass the MoT test – many readers report that, after theft (because of the precious metal content of the cat), they have sourced straight pipes instead of a new cat, saving hundreds of pounds.

However, even if the tailpipe emission test is within the limits, the motorhome will fail, so beware.

On the emission (smoke) test, older motorhomes will benefit from a hard drive before the test – hold a gear in higher revs longer than you would normally before swapping cogs.

This will help burn off excess carbon that may cause a fail during the test.

Get inside

Moving inside, the MoT test covers the door latch and all seatbelts, including child seats/restraints.

This is a visual inspection for defects on webbing, stitching that’s frayed or repaired, cuts or deterioration, and anchorage points and buckles.

For seatbelts attached to the seats, a cracked or damaged seat frame would be reason for failure.

The driver’s seat must be secure and adjustable, and the SRS (airbags), seatbelt pretensioners and seatbelt load limiters, as fitted as original equipment, will be visually examined.

The driver’s view through the windscreen mustn’t be obstructed, and any chips elsewhere on the glass should be fixed as soon as possible (often covered by comprehensive insurance).

There are also grounds for refusing to test a vehicle – major reasons being that it’s not fit to drive, the vehicle emits substantial quantities of avoidable smoke, or there’s a lack of fuel or oil.

Finally, a test certificate only relates to the date and time of inspection, and should not be taken as a guarantee of roadworthiness if you are buying pre-owned.

Technical work can be dangerous – take adequate safety precautions before proceeding