Trailer plug test for NCT?

dooroy

A friend of mine has a 2000 Bora Tdi . It went for NCT just before Christmas and one of the fail points was the trailer lights socket ' not working properly'.

This is the first time this has happened - car has been going through the test with this towbar and socket for years. All the lights work on the trailer - and I can't find any mention of the trailer socket in the NCT manual available on line.

Anyone else come across this - do they plug in some kind of tester to socket ??
Any help appreciated .

CJhaughey

dooroy wrote: »

A friend of mine has a 2000 Bora Tdi . It went for NCT just before Christmas and one of the fail points was the trailer lights socket ' not working properly'.

This is the first time this has happened - car has been going through the test with this towbar and socket for years. All the lights work on the trailer - and I can't find any mention of the trailer socket in the NCT manual available on line.

Anyone else come across this - do they plug in some kind of tester to socket ??
Any help appreciated .

Page 103
http://www.rsa.ie/Documents/NCT/New%202018/NCT%20Manual%202018.pdf

Test plugs are widely available, they light up to show the various functions of the socket pins are working.

dooroy

Thanks for that cjhaughey - was looking in sections dealing with towbar and no mention of the socket.
Now I know whats needed:).

Doctors room ghost

I tested my current car twice and all it has is a tow bar and the wire for lights is cable tied under it as the socket broke off.no hassle with it

dooroy

This Bora has gone through the test for many years with the same towbar and socket - never a problem. New 'additions' to test I take it .
If there was no socket it would be OK I presume - but once it's there it will be checked.
The seven pin socket has a pin for foglights - so I presume this will have to be connected even though the trailer lights have no foglight in them.

mgbgt1978

Specifically says only Brake, Indicator and "position lights" (Tail lights basically) are checked.
From that It's hard to see how a missing fog light output can be a fail. Any hassle, just show them their own manual

dooroy

Thanks mg- hadn't noticed that bit.
Will have to check as seen a few cars where both 'position lights' were fed by the same pin - so that might be the problem:)

Irish Steve

dooroy wrote: »

Thanks mg- hadn't noticed that bit.
Will have to check as seen a few cars where both 'position lights' were fed by the same pin - so that might be the problem:)

The trailer socket test is relatively new in the system, and is also being applied to the CVRT as well.

If both position lights are being fed from the same pin, and the other pin in the socket is not wired, then that will be a fail, as it's not according to the standard wiring for a 7 pin socket, and one of the position lights on the test rig will not work.

The other issue which can occur is if the earth pin is either not connected, or corroded, (corrosion is common), if the trailer lights are earthed to the chassis as well as through the wiring, when the trailer is on the vehicle, the lights may work as the hitch may provide an earth, but the test bar or test plug will not work correctly if the socket earth is bad. This is most common where a self tapper is used through the light to a steel frame, in some cases, the self tapper becomes an earth if it's put through the structure of the light, and that can well confuse things when testing.

The other issue that can cause problems is on the newer cars that have CANBUS connected lights, I've seen the trailer unit put into the wing at the back, but the problems then start if water gets into the wing, and the control unit, all sorts of strange faults can then occur due to corrosion and shorting caused by the water getting into the unit.

dooroy

Have been asked to sort out trailer lights on a few older cars - and they can be a nightmare due to corrosion , poor connections etc . Sometimes the problems appear when the car is changed - this happened me twice ; the trailer socket was wired completely wrong , then the trailer plug was wired to suit the socket and get lights ; all well until the car was changed and the next car had the trailer socket wired correctly - you couldn't make it up .
I keep away from newer cars if they have the unit in the boot.

Irish Steve

Been there, done that, shredded the T shirt, more times than I care to remember.

The other possible and common issue is that the wiring may have been put in with Scotchloks, which are notorious for corroding over time, and not working correctly. If they are internal to the wing, there's not so much of an issue, but the number that get put on to wiring around the towbar area, so exposed to all the elements under the back of the vehicle, it's a wonder they work at all, let alone for any length of time.

mgbgt1978

dooroy wrote: »

Thanks mg- hadn't noticed that bit.
Will have to check as seen a few cars where both 'position lights' were fed by the same pin - so that might be the problem:)

Irish Steve wrote: »

The trailer socket test is relatively new in the system, and is also being applied to the CVRT as well.

If both position lights are being fed from the same pin, and the other pin in the socket is not wired, then that will be a fail, as it's not according to the standard wiring for a 7 pin socket, and one of the position lights on the test rig will not work.

Only problem with this set-up is that ANY Trailer you tow must be wired to match it for both tail lights to operate. It would be very strange for a Tow Bar Fitter to wire the Socket this way.

What usually happens (and shouldn't) in practise is that the Black and Brown wires (the L/H and R/H Tail lights) are simply joined and either connected to the R/H Car Tail Light or L/H. Not really a major issue (and certainly not noticed by the NCT). Just that most cars have separate L/H and R/H circuits so that at least one tail light will operate if a fuse blows......

Irish Steve

This is one of those catch 22's. If the plug is wired incorrectly, then there will not be an issue with the test system at the NCT/CVRT, as they are wired to check both circuits are alive when they are supposed to be. The problem comes if the socket has one of the 2 pins floating, and not connected, then the test equipment will show a fail.

In the second case, a correctly wired trailer will not work correctly.

The only other issue may be if there is a failure that blows a fuse, if the trailer or the socket is wired incorrectly, then it may be the case that nothing on the trailer works, which is clearly not a good situation. If the vehicle has relatively low fuse ratings, then it's also possible that a wrongly wired trailer could blow the fuse even if there is no fault as such.

shane b

Had my 06 Avensis in for NCT on Monday and it failed on the towbar lights not working correctly. Happy enough that's all it failed on but just a pain it was never picked up before. got someone to look at it today and it seems 2 of the wires were in the wrong position. Have the car 5 years and the towbar was on the car when i bought it. Hopefully it will pass next week now.

dooroy

I have got a tester and hope to check the Bora soon for the retest.
This guy has this car for 8 years - towbar and socket were there when he got it and have worked fine ever since. And trailer lights were OK .
So I'm curious to see what the problem is - I think testing the socket is a recent addition to the checks.

TrailerBob

It's is very recent. Had the wife's Kuga in for a test yesterday and failed on the trailer socket. I never checked it as it has towed a trailer twice in the 5 years we have it. No need with a landcruiser in the house. It's almost always corrosion in the terminals. Strip the wires, clean the terminals and reconnect.

TrailerBob

Now the strange bit... I've tested the socket and everything functions exactly as it should... Plugged into trailer.. all working.. tested each terminal with a circuit tester.. all working.. yet Mr NCT man said it's not working... Hmmm

Irish Steve

TrailerBob wrote: »

Now the strange bit... I've tested the socket and everything functions exactly as it should... Plugged into trailer.. all working.. tested each terminal with a circuit tester.. all working.. yet Mr NCT man said it's not working... Hmmm

Very possible if the socket is rarely used. Had a horsebox recently that had no lights working correctly, checked the socket out with a meter, and all good, then checked out the cable from the vehicle to the socket mounted on the front wall of the box, again, with the meter, all good.

Took the socket off the front wall, and checked on the back of the socket for earth back to the vehicle, no connection, and on digging closer, the issue was corrosion inside the receiver pin on the socket, so while there was a good earth in the cable, the connection from the cable to the wiring downstream of the second socket was open circuit.

10 minutes with emery cloth wrapped round a small screwdriver, and everything was working, so while in theory the meter may show a good connect, when connected through the correct plug and socket, it might not work correctly.

Are both side light circuits working on the socket, if the trailer has been wired to light both lights off the one pin, if the other pin is not live, that won't show on the trailer, but will show on the test rig.

The other possibility is that the plug on the NCT centre test rig may need the pins opening out again to ensure a good connection to the socket, if you can show it's working on either a light bar or your tester, they may not push the point.

We ended up making a long lead test rig a few weeks ago, due to the number of test fails that were coming in, being able to put the box on the ground and see it from the driver's seat makes testing a one man job, and it also has the facility to test a trailer using a 12 V battery, with a switch and light for each circuit, it's paid for itself already in terms of time saved testing vehicles.

TrailerBob

I reckon it's the pins being a bit closed alright. I've opened them out and all should be well. It's all wired correctly for certain

Hellrazer

What centre was it in Trailerbob--I had a few fails in the last 2 weeks all in the same NCT centre.

Ended up buying a trailer board for the workshop so we could test ourselves. NCT failed one car 3 times yet it was all working correctly on our trailerboard.

Brought the board with us and showed them it working and it turns out their tester was faulty. The NCT are using some sealey tool for testing.

They passed both cars after seeing them working on our board.

johnayo

Hellrazer wrote: »

What centre was it in Trailerbob--I had a few fails in the last 2 weeks all in the same NCT centre.

Ended up buying a trailer board for the workshop so we could test ourselves. NCT failed one car 3 times yet it was all working correctly on our trailerboard.

Brought the board with us and showed them it working and it turns out their tester was faulty. The NCT are using some sealey tool for testing.

They passed both cars after seeing them working on our board.

But are the LH and RH tail light wires connected together in the Trailer Socket. Your lighting board would work fine but it would rightly fail with the Sealey tool.

Hellrazer

johnayo wrote: »

But are the LH and RH tail light wires connected together in the Trailer Socket. Your lighting board would work fine but it would rightly fail with the Sealey tool.

That makes sense. I honestly cant remember.
Its quite possible that they were wired together and the sealey tool showed a fail.

They gave us the pass when we showed up with the trailer board though.

TrailerBob

Carlow Town... I reckon there'll be a lot of fails on this for a while!

Melodeon

Yep, half the cars on the road with trailer sockets never tow anything so they're never used and they're likely well corroded and borked, and a goodly number of those that are used are 'creatively' wired to match the equally creative wiring on their trailer.

TrailerBob

I'm actually glad they are testing it. It's something I'm absolutely anal about is trailer lights not working. So many on the road!

Eric Cartman

Anyone who actually has a failure / mangled socket / electrics not fitted should take the opportunity to wire up a new 13 pin socket, they fixed the sealing issues that cause most corrosion, floating ground and back feeding issues, you can still get 7 pin adapters and theyre cheap so become the sacrificial lamb for broken trailer plugs or fault wiring

dooroy

I had to put a new socket on the Bora - and like many cars both parking lights on the trailer work of one pin ; so I bridged the pins in the socket.
The tester I have is a Sealey one and it must show 2 lights for the parking lights - which it does now. Retest later today .

popacam

I thought it wouldnt be an issue if the socket was removed but a phone call to the NCT confirmed that the towbar and "all evidence of a towbar" would also need to be removed.

mullingar

popacam wrote: »

I thought it wouldnt be an issue if the socket was removed but a phone call to the NCT confirmed that the towbar and "all evidence of a towbar" would also need to be removed.

Not according to manual:

Section 61:

http://www.rsa.ie/Documents/NCT/NCT%20Manual%20Revise%20JULY%202014.pdf

Method of Testing
1. Check that the registration number plate lamp(s) shows a white light and is operating effectively. Check trailer
electrical sockets (where fitted) for; security, damage or deteriorated insulation.
2. Check the outputs from socket (only applies to Brake, indicator and rear position lights).
Advisory Pass applies where there is a defective light source (multiple light source or in the case of LED up to 50%
not functioning).
NOTE:
1. Some 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 socket.
2. A trailer electrical socket with a defective or missing cover flap that incorporates a lug and spring to
hold the plug in place is not a reason for failure.
ITEM REASONS FOR FAILURE SEVERITY
Registration Plate
Lamp
(a). Lamp is not fitted/missing or is not securely attached.
(b). Lamp so insecurely mounted that there is a serious risk of it falling off.
(c). Lamp is not white in colour when operational.
(d). Lens broken, missing or badly cracked.
(e). Lamp showing direct (not reflected) white light to the rear.
(f). Defective light source, (single light source or in the case of LED less than
50% functioning.)

Trailer Light Socket
outputs
(g). Socket or components not securely attached.
(h). Socket/components so insecurely mounted that it is likely to fall off.
(i). Damaged or deteriorated insulation.
(j). Damaged or deteriorated insulation that it’s likely to cause a short-circuit
fault.
(k). Trailer or towing vehicle electrical connections not functioning correctly.
(Incorrect or no outputs from socket).

Nothing about the socket missing = failure

Melodeon

I haven't researched this at all, but I'd be amazed if wasn't illegal to have a tow hitch on a vehicle without a socket for trailer lights.
Perhaps it's something along those lines?

Hurrache

popacam wrote: »

I thought it wouldnt be an issue if the socket was removed but a phone call to the NCT confirmed that the towbar and "all evidence of a towbar" would also need to be removed.

mullingar wrote: »

Not according to manual:

Section 61:

http://www.rsa.ie/Documents/NCT/NCT%20Manual%20Revise%20JULY%202014.pdf





Nothing about the socket missing = failure

All traces of the tow equipment need to be removed. I was going to try just take off the socket myself on a car a few months ago. I rang the call centre a couple of times and asked a few guys working there, it all has to be gone.

mgbgt1978

Looks like the NCT have decided to interpret the RSA's Rules incorrectly. Plenty of 2nd hand Cars out there with just the visible part of the towbar removed prior to Sale....to avoid any awkward questions from potential Buyers.
The rest of the towbar will be visible once the Car goes up on the NCT Ramp:).

I'd love to know what Fail Code they intend to use if a socket is missing. It's not listed in the manual and AFAIK they cannot just make up a 'reason for failure'....it must be a particular fail complete with the appropriate Reference Number.

Whocare

Has a commercial pickup going through to cvrt and just remove the plug and I passed

Hurrache

mgbgt1978 wrote: »

I'd love to know what Fail Code they intend to use if a socket is missing. It's not listed in the manual and AFAIK they cannot just make up a 'reason for failure'....it must be a particular fail complete with the appropriate Reference Number.

I tried argue this, but got nowhere really even after speaking with supervisors. In the end it was just easy for me to remove it temporarily.

I do see the logic behind failing it though, I was arguing on the point of semantics.

mgbgt1978

I do agree with you on the semantic aspect. If it's not a specific fail then that's not your fault.

mgbgt1978

Melodeon wrote: »

I haven't researched this at all, but I'd be amazed if wasn't illegal to have a tow hitch on a vehicle without a socket for trailer lights.
Perhaps it's something along those lines?

Prepare to be amazed . The only legislation seems to concern 'E'-markings on towbars....and even that seems to be merely a proposal.

mullingar

Nct can't fail on anything that's not mentioned as a fail in their book. If they do fail, they must advise under which section it failed on if you ask. The absence of a socket is not a fail and the manual clearly states 2 little words that makes all the difference "where fitted"

TrailerBob

So if I'm reading the posts here correctly, a lot of people are just going to remove their trailer socket to pass the NCT instead of a) checking if it works or b) fixing it if it doesn't.. so that when they do get around to towing a trailer they have no lights at all... Real Irish solution...

It's not that hard to have it working.

Hurrache

You're reading of it is incorrect. In my case we never have, and don't intend to in the near future, towed anything, the hitch was on the car when we bought it. It was never flagged in previous NCTs, nor did we notice it due to the aforementioned non use.

But any assumption to allow some people take the only in Ireland stance I suppose.

Tacitus Kilgore

Hurrache wrote: »

You're reading of it is incorrect. In my case we never have, and don't intend to in the near future, towed anything, the hitch was on the car when we bought it. It was never flagged in previous NCTs, nor did we notice it due to the aforementioned non use.

But any assumption to allow some people take the only in Ireland stance I suppose.

TB is still correct though, it doesn't take much longer to rewire a trailer socket than it would to remove one...


You never know, some day you might need to pull a trailer, and that day you'll have no lights..

Hurrache

Tacitus Kilgore wrote: »

TB is still correct though, it doesn't take much longer to rewire a trailer socket than it would to remove one...


You never know, some day you might need to pull a trailer, and that day you'll have no lights..

It's wildly incorrect to suggest it doesn't take that much longer to remove a socket than rewire one. 1 minute and you'll have the socket off, but if there's no power to your socket and it's not a simple matter of power in the loom but not the socket itself and the fuse is fine, balls if I was going to remove a whole load of trim and trace the wiring.

But you're right, they should fit tow hitches to all vehicles from now on, because you just never know.

Tacitus Kilgore

Hurrache wrote: »

It's wildly incorrect to suggest it doesn't take that much longer to remove a socket than rewire one. 1 minute and you'll have the socket off, but if there's no power to your socket and it's not a simple matter of power in the loom but not the socket itself and the fuse is fine, balls if I was going to remove a whole load of trim and trace the wiring.

But you're right, they should fit tow hitches to all vehicles from now on, because you just never know.

Jesus sounds like a bastard of a setup in yours, what is it?

I don't need to remove any trim, just pop out a taillight and attach a couple of splices, doesn't take much more than a few minutes for me.. Then again it's not being taken off a loom, or a canbus setup. Even still, would absolutely kill me to know that it wasn't right.

joujoujou

Hardly a need of socket if one using a towing hitch solely as a simple parking sensor.

Hurrache

Tacitus Kilgore wrote: »

Jesus sounds like a bastard of a setup in yours

It was installed by the dealer and the wiring is well integrated. I managed to track it bask as far as merging with the headlight loom but it's fed through the floor and under the trim of the boot/boot lip. Trim doesn't pop off like the rest of the trim around the boot and I gave up when I got back as far as the rear light cluster before disappearing into the body from that point in.

joujoujou wrote: »

Hardly a need of socket if one using a towing hitch solely as a simple parking sensor.

Car has parking sensors, but it was put back on as a protection against the cars that don't

Claude Burgundy

I'm looking to put a tow bar on my car for a bike rack. I have no intention of ever putting a trailer on.

Do i need the light socket wired for the NCT ?? Will it fail with no socket at all ?

Hurrache

It seems at one stage it may have depended on the tester, but based on my experience at a test centre and with the NCT call centre, it you have a tow bar you need a working plug socket, they wouldn't pass mine if I just removed the socket and left the bar there.

joujoujou

Claude Burgundy wrote: »

I'm looking to put a tow bar on my car for a bike rack. I have no intention of ever putting a trailer on.

Do i need the light socket wired for the NCT ?? Will it fail with no socket at all ?

Towbar without a socket is a fail. Weird, especially that socket without a towbar is perfectly fine.

Just get the one you can easily remove before a test.

mgbgt1978

Claude Burgundy wrote: »

I'm looking to put a tow bar on my car for a bike rack. I have no intention of ever putting a trailer on.

Do i need the light socket wired for the NCT ?? Will it fail with no socket at all ?

I'm not telling you what to do....and it doesn't matter to me in the slightest.
But, if your lights are obscured at all by your bicycle (and they will be if it's a towbar-mounted carrier) then you are required to mount a Lighting board as well. Oh, and a number plate if your's is even partially hidden.
As I said, not my business....but you might just p1ss off the wrong Guard some day .

joujoujou

Sorry, I misled you. If socket does not exist, it's not tested. Hence no fail. Screenshot from NCT manual (see highlighted bit):

mgbgt1978

Not according to some posters on this thread. They claim that the NCT have told them that if a towbar (or evidence of a towbar) is fitted then there must also be an electrical socket fitted...which is then tested.
I know it's not in the NCT manual. and I have already stated that as there is no fail code for a missing socket then they cannot fail you, but some people are saying different.


edit: unless they are stretching the Rules and going with (k).

FDave

I'd assume the failure is covered by section 25 of the NCTS manual

mgbgt1978

No mention of electrics of any sort there FDave. Mechanical stuff mainly.