This inspection applies to: all types of towbar fitted to the rear of a vehicle. It does not include emergency towing eyes.
If a tow ball or pin is not fitted at the time of test, e.g. because it is detachable, has been unbolted or otherwise removed, but the attachment brackets are still in place, these brackets should still be assessed unless they have been deliberately rendered unfit for further use.
There may be play in some detachable tow balls between the receiver socket and the tapered swan neck fitting, with up to 3mm movement measured at the ball end. Reason for Rejection 4a should only be used where play is greater than this. Quick release mechanisms must not be operated, only visually assessed.
- Visually assess the towbar for wear and pull on the towbar and/or its mountings to check for security, corrosion, fractures or damage
- Check the towbar assembly is attached to the vehicle structure using mountings, supports and fixings of an appropriate size and type
- Check the presence and security of:
- retaining devices e.g. nuts & bolts
- locking devices e.g. split pins, ‘R’ pins
Note: It is not always possible to determine the presence and effectiveness of certain types of locking devices eg locking fluid or ‘nyloc’ nuts.
On detachable tow balls:
- Check for play between the tow ball arm and its receiver socket
- Visually assess the condition of any quick release mechanism
Many ‘bolt-on’ type tow balls have accessory devices sandwiched between the tow ball and its mounting flange. These are not to be considered as inappropriate modifications unless their fitment is clearly likely to adversely affect the roadworthiness of the vehicle/trailer combination.
Trailer electrical couplings are tested under Section 1.9.
This inspection applies to all vehicles, including electric and hybrid vehicles.
Some tow bar electrical sockets are ‘hidden’ behind an access panel in the bumper or bodywork. Unless requiring the use of tools or specialist equipment, these panels must be removed to facilitate the inspection of the towbar socket.
If a tow ball or pin is not fitted at the time of test, e.g. because it is detachable, has been unbolted or otherwise removed, but the attachment brackets are still in place, any trailer electrical socket should still be assessed.
This does not apply if the attachment brackets have been deliberately rendered unfit for further use.
On vehicles fitted with a trailer 13 pin Euro-socket, use an approved device to check that the socket is wired to correctly operate the trailer:
- Position lamps
- Stop lamps
- Direction indicators
- Rear fog lamp
- On vehicles fitted with a towbar, check the condition and security of the trailer electrical socket
Note: This check applies to both 7 pin (12N) and 13 pin electrical sockets
A trailer electrical socket:
- Damaged or deteriorated to the extent that the connecting lead could not be securely connected
- A trailer 13 pin Euro-socket not operating the trailer lamps as intended