Brake Lights Not Working

DaveA1963 · Member

Brake Lights Not Working

erad · Guru

Open the trailer plug and check the wiring connections. The standard connections are:
1 Left turn - Yellow wire
2 Reversing lights - Black wire
3 Earth - White wire
4 Right turn - Green wire
5 Electric brakes - Blue wire
6 Stop lights - Red wire
7 Tail lights etc - Brown wire

It is common practice to use Pin No 2 as the hot wire for 12 Volts to the caravan (interior lighting). Probably the previous owner had the wires to No 5 & 6 the wrong way round (or maybe your car is the wrong way)?.

Possum3 · Guru

Easy read diagrams at:

www.trailersrus.com.au/guides/technical-guides/australian-trailer-plug-and-socket-wiring-diagrams/

DaveA1963 · Member

Thanks for that info guys - very useful!

I suppose it's also possible that the adapter is mis-wired, but anyway, I'll check all the "pinouts" and ensure the right wires are in the right holes. I'll be running an Anderson Plug for all the heavy-duty 12V supply duties between tug and van and will keep the trailer plug for what it's designed for!

PeterD · Guru

Dave, the auto-calibrate in your Redarc brake controller is about setting up the decelarometer before you hitch up a van with brakes. It has nothing to do with the setting of the controller to suit the trailer brakes. Have you got a Dexter trailer anti-sway unit in your van? Redarc controllers do not work with those unless you put a fiddle in the circuit. The controller will not wake up when you brake unless there is a load on it. The Dexter anti-sway does not put a load on the controller. You need one of these wired across the input to the anti-sway controller to wake the Redarc up when you put your foot on the brake pedal.

The others have given you the pin connection numbering for the different trailer connectors. I don't think we can offer much more to you. It is now a case of you or someone else chasing out the problem with a meter or a test lamp.

dabbler · Guru

Another possibility: The pins are notorious for being squeezed closed when the plug is wiggled sideways to connect or disconnect. Outer pins are most susceptible but any pin can be affecfed. A thin bladed screwdriver inserted into the compression slot (the slot is there to help lock contacts in place) then twisted slightly will spread them apart and return the pin to the needed diameter to make good contact.

erad · Guru

Further to Dabbler's comments above, EVERY Time I hook up the caravan or trailer, I get someone to check that the lights on the van are working properly. You never know if the bulb has blown or, as said above the connecting pins are not making contact. It is a one minute job and if it saves someone from running into the rear of my caravan, it is time well spent.

Instead of using a fine bladed screwdriver, i find that a pocket knife works better to spread the fingers on the connecting pins in the plug.

oldbloke · Guru

I had no end of problems with brakes. I test every time I tow now.

1. Set red arc at about 6 to 8
2. Apply bakes moderatly at about 10kph
3. It should be very obvious that the van is stopping the car. On gravel they will lock up.

4. Set the red arc at about 4. You will need to make the final adjustment. But 4/5 works for me

5. Drive off and press the over ride button, it should apply the brakes moderately.

Not finished yet.

A. Now drive down the road

B. After driving around streets/suburbs or down a hill for a few k

D. Stop, get out and check all drums are warm or hot.

E. All drums should be roughly same temperature

This is over the top. But after having them "installed" incorrectly, (3 times) in compatible controller fitted, and "repaired" several times. I am now convinced most so called service centres don't give a rats ars if you die due to their complete and utter incompetence.

Only go to an auto ectrician preferably one that has been recommended. Unless you have a high level of confidence in a mechanic.

Good luck and take care.

Finally, check for a common earth or brake earth wire on the van. If its dodgy brakes will play up/not work. I Had that too.

Edit,: Red arc web site has a page listing what units are compatable with various esc/brake systems.

-- Edited by oldbloke on Wednesday 27th of January 2021 11:52:50 PM

Steel Dog · Veteran Member

I had one the sockets, not the pin, it was pushed in and the pin could not reach it to make contact, you have to look carefully to see which one.

DaveA1963 · Member

Can't work out how to delete this post - my reply is below...

-- Edited by DaveA1963 on Thursday 4th of February 2021 08:10:34 AM

DaveA1963 · Member

PeterD wrote:
Dave, the auto-calibrate in your Redarc brake controller is about setting up the decelerometer before you hitch up a van with brakes. It has nothing to do with the setting of the controller to suit the trailer brakes. Have you got a Dexter trailer anti-sway unit in your van? Redarc controllers do not work with those unless you put a fiddle in the circuit. The controller will not wake up when you brake unless there is a load on it. The Dexter anti-sway does not put a load on the controller. You need one of these wired across the input to the anti-sway controller to wake the Redarc up when you put your foot on the brake pedal.
The others have given you the pin connection numbering for the different trailer connectors. I don't think we can offer much more to you. It is now a case of you or someone else chasing out the problem with a meter or a test lamp.

Hi Peter. Ah hah! Yes, that rings a bell! There is a "box" I noticed in passing that I don't recognize, so that could be the Dexter unit. I know the van has a breakaway controller, so maybe that's what I'm thinking of, but I'll check when I get a chance (we're in the middle of getting our house ready to sell and I'm frantically renovating and painting, painting, painting and The Boss won't let me play with the van at present biggrin )

The previous owner replaced the tail lights with LED's so that could also be a factor. I have a very knowledgeable mechanic/guru who is also a caravanner and I'll be taking the van to him when I get 5 minutes and hopefully he can work out what's wrong. I'd at least like to get the brake lights working, at the very minimum, before I head back out on the road. Having the brakes working would be even better!

I'll also make sure to check the plugs and contacts for damage to ensure good connectivity.

Thanks again to everyone for the great advice. This is what a good forum is all about!

-- Edited by DaveA1963 on Thursday 4th of February 2021 08:18:49 AM

Bill B · Guru

PeterD wrote:

Have you got a Dexter trailer anti-sway unit in your van? Redarc controllers do not work with those unless you put a fiddle in the circuit. The controller will not wake up when you brake unless there is a load on it. The Dexter anti-sway does not put a load on the controller. You need one of these wired across the input to the anti-sway controller to wake the Redarc up when you put your foot on the brake pedal.
T

May have been the case with the first Tow Pro's but this doesn't apply to latest version ( V3) which has been out for at least 2 years.

From Redarc site :

Compatible with all modern vehicles

When used with the recommended REDARC wiring kits, the Tow-Pro Elite ensures compatibility with all new vehicle technology and features Active Calibration. It works in 12V vehicles with Electric or Electric/Hydraulic trailer brakes and it works in 24V vehicles with electric brakes without the need for any additional adaptors.

For Electric/Hydraulic brakes behind 24V vehicles, it requires the EB24A adaptor. When installed as per instructions It ensures an ADR approved installation. It has also been approved by AL-KO for use with their ESC and by Dexter with their DSC systems.

PeterD · Guru

Bill B wrote:
May have been the case with the first Tow Pro's but this doesn't apply to latest version ( V3) which has been out for at least 2 years.
From Redarc site :

Compatible with all modern vehicles
Snip

Bill, you know not what you are talking about. The information I posted comes from personal experience.

Firstly, the acclaimed Tow-Pro Elite released in September 2015. That means my equipment is not a model before the V3 was upgraded. Like the OP's situation, my newly acquired tug worked OK before I hitched the van up to it. Also, the brakes were working on the van before I first towed it. (My situation is the opposite way around in that the new vehicle is the tug where his new vehicle is the van, but the situation is identical as to how things are/were panning out.)

From the Tow-Pro Elite V3 Instruction Manual:-

Immediately After Installation (To be done by a qualified Auto-Electrician)
Test the installation/vehicle wiring. Testing your vehicle wiring is best done by connecting
a test light (Max 21W filament globe) to the brake output, pushing the manual override and
having someone check that the test lamp lights up.

That test instruction is necessary because You can't test the Tow-Pro with a volt meter. You will not see any voltage at the trailer socket until the controller wakes up. The controller will not wake up unless there is a solid load on it.

From Redarc's website:-

Tow-Pro Technical Bulletin

Tow-Pro not detecting trailer

Read through that. The Dexter anti-sway does not connect the brake magnets to the trailer plug until you wake it up with a significant voltage to its input

-- Edited by PeterD on Thursday 4th of February 2021 09:24:53 PM

Bill B · Guru

PeterD wrote:

Have you got a Dexter trailer anti-sway unit in your van? Redarc controllers do not work with those unless you put a fiddle in the circuit.

Have V3 Tow Pro in tow vehicle and van has Dexter sway control fitted and brakes work fine without putting a "fiddle" in the circuit.

Whenarewethere · Guru

DaveA1963 wrote:
although it's only three months old

A lot of cars run on a CAN bus system. A lot of cheap LED globes will not work. Make sure the globes are the same type the car uses. If that works then try with a LED globe suitable for a CAN bus system.

Land Rovers use CAN bus & the wrong LED globes in the car or trailer will not work.

-- Edited by Whenarewethere on Thursday 4th of February 2021 11:56:36 PM

PeterD · Guru

Bill B wrote:
PeterD wrote:
Have you got a Dexter trailer anti-sway unit in your van? Redarc controllers do not work with those unless you put a fiddle in the circuit.
Have V3 Tow Pro in tow vehicle and van has Dexter sway control fitted and brakes work fine without putting a "fiddle" in the circuit.

Did you install your own Dexter unit? If it was installed by another, was the resistor installed as part of the installation by the installer as he knows of the problem? You would not know the answer to the second question unless you ask the installer. The paper issued by Redarc pointing out the problem does not mention any changes to the V3.