Hitching, lights and number plates

By the end of this topic you can

• You can couple a trailer to a tow ball and check it is secure.
• You can attach a breakaway cable or secondary coupling correctly.
• You can connect the trailer electrics and check every light works.
• You can fit the correct number plate to a trailer.
• You can carry out tyre and mirror checks before towing.

What you need to know and understand

• You must use a breakaway cable or secondary coupling in case the trailer becomes detached.
• A breakaway cable applies the trailer's brakes, if fitted, or stops the trailer if it comes off the car.
• Trailer electrics connect through a 7 or 13 core cable and plug, which must not be damaged.
• All trailer lights must be working correctly before you tow.
• Your trailer must show the same number plate as the towing car.
• You can be fined up to 1,000 pounds and get 3 penalty points for towing without proper towing mirrors when they are needed.
• A tow bar fitted to a car first used from 1 August 1998 must be type approved.
• Trailer tyres need at least 1.6mm of tread across the central three-quarters of the tread, all the way round.

Coupling up step by step

Always follow the trailer maker's instructions, as couplings vary. The general order is below.

1. Park the car on firm, level ground in line with the trailer and apply the trailer's handbrake.
2. Use the jockey wheel to raise the trailer's hitch above the height of the tow ball.
3. Reverse slowly, with a helper guiding you if possible, until the tow ball is under the hitch.
4. Lower the hitch onto the ball until the coupling locks. Many couplings show a green indicator when locked.
5. Check it is secure by winding the jockey wheel down slightly to lift the car's rear a little. If the hitch stays on, it is locked.
6. Raise and fully stow the jockey wheel so it cannot touch the road.
7. Attach the breakaway cable or secondary coupling, then plug in the electrics.
8. Release the trailer's handbrake before moving off.

Breakaway cable and electrics

Clip the breakaway cable to a proper attachment point on the tow bar, not around the tow ball neck unless the maker allows it. Leave enough slack so it does not pull the brakes on when you turn, but not so much that it drags on the ground. Check the cable for wear.

Route the electrical cable so it has room to flex on tight turns without touching the ground or getting trapped.

Lights, plates, tyres and mirrors

With a helper, check side and tail lights, brake lights, indicators on both sides and the number plate light. If an indicator fails, the trailer is not safe to tow.

Fit a plate showing the car's registration to the back of the trailer. Check tyres for cuts and bulges, inflate them to the maker's figure for the load, and check the wheel nuts are tightened correctly and the mudguards are secure.

Fit suitable towing mirrors if the trailer or caravan is wider than the rear of your car. Adjust them so you can see down both sides of the trailer.

Uncoupling

Reverse the order: park on level ground, apply the trailer handbrake, unplug the electrics, remove the breakaway cable, lower the jockey wheel and wind it to take the weight, then release the coupling and lift the hitch clear before driving away slowly.

Common mistakes

• Not checking the coupling has locked. Always do the lift test with the jockey wheel.
• Leaving the jockey wheel down or loose. It can hit the road and damage the trailer.
• Fitting the breakaway cable too tight, so it applies the brakes on bends.
• Using a number plate from a different car. It must match the towing vehicle.
• Towing a wide caravan with standard mirrors. Fit towing mirrors when the trailer is wider than the car.

Test yourself: Hitching, lights and number plates

Answer each question, then read the explanation. Questions come in a random order each time.