So, I've fitted my LR OEM twin tow electrics kit (ECU Plug & Play) and it's not working - help! (12N & 12S)

I fitted exactly as the LR instructions, have plugged and re-plugged all connections. Checked every fuse with multimeter and made sure they are in the correct locations (2x15 and 1x40 little green cube). Earth wire is connected and I have also tried connecting it direct to the battery negative terminal to eliminate the possibility of a bad earth.

Fuse on the ECU board is good and showing 12v on both legs (measured from exposed pins without removing fuse).

On the 12S white socket, I can pick up a solid 12 volts on one pin and just 4 volts on another.

On the 12N black socket, I can only pick up 4 volts on the live pins (depending on which lights I have chosen to test).

Help - why only 4 volts? Appears everything is working and connected OK, but I can't get a full 12 volts where and when I need it - EXCEPT the permanent live on the 12S white socket).

I have not yet had it configured by LR, but it should still at least work in it's basic functions.

Anyone?

I recall on Pre MY13's you have to have the electrics enabled by a Dealer ( I Did )
On my MY13 it is a true plug N play - assuming the fuses are in place.

what year is your's? 

I'm on a 2011 facelift manual Td4.

I thought that the dealer programming only disabled rear sensors and added dash lights etc. I believed it should at least function to be able to tow immediately?

2008 auto
It plugged and played for me

When measuring voltage have you tried putting the negative prob to a good car earth

Yes, I'm actually taking a long fly lead all the way back to the negative terminal on the battery and connecting to multimeter.

It feels like there's 12v available (ie, direct through 12 S socket), but for some reason, everything that's live only when applicable, is just 4 volts.

I fitted my towbar and LR electrics exactly as you have and nothing worked until after a visit to the dealer whereupon all worked. That is on a 2011MY. So I suspect that there is something more than just the parking sensors.

This may be can-bus related. It is possible that your meter is not drawing enough current for the can-bus to recognise the connected circuit. A similar problem occurs with LED lights on a trailer where they draw insufficient current for the can-bus to recognise a bulb. Most professional installers use a trailer board to test, possibly because of this problem.
To prove or disprove this you could try connecting a 12v filament bulb to each circuit to test. You could also then connect your meter across the bulb to check voltages.
I believe the permanent 12v supply is a straight through feed.
Hope this may help,

Steve

I started by connecting my trailer which has regular filament bulbs (known good circuits, bulbs and connection cable) and nothing lit up. Then I measured at the socket and then at the other end of the good connection cable, same

Didn't want to send it into LR until the next service due in the summer, then was planning to have it programmed.

I had exactly the same as you on my MY2011 SD4. Only the live feed.
Once I visited the dealer and paid for half an hour of diagnostic time, everything worked as it should.
This was with genuine Land Rover electrics - plug and play.
They did wash it for free as well.

Thanks guys.

Appears to be a mixed bag of some work, some don't, but all perfect after main dealer diagnostic / programming.

So I guess I'll get myself booked in for a wait in the coffee area and hopefully a free car wash!!

I'll update knowledge bank once completed.

[quote="cqr"]2008 auto
It plugged and played for me[/quote]

Had the previously had a towbar? Mine was plug and play but that is because it appears to have had a towbar fitted in the past at some point so had already had the programming done.

You will need to have it programmed for it to function correctly. Freelander 2 HSE Lux 2013MY - Barolo Black with Ivory Leather. Alpine DVD - Privacy -Evoque 20" Dynamic Wheels and more to come.........

So, the plot thickens!!!!

Have now had the main dealer enable the tow electrics and they kind of work but something's not right.

When I put on the hazzard warning, just the two brake lights blink together on trailer (car as normal,all orange).

When I indicate LEFT, nothing happens, when I indicate right, BOTH brake lights blink (again, all is fine on the car).

Side lights work correctly.

I have two different new trailers, both of which act the same way and both are perfectly fine on every other car I try them on.

How can this be wrong? There is no wiring to get wrong on the module, it's all pre-wired and PLUG-n-PLAY, even the multipin 12N and 12S connections.

Are there different settings that the main dealer can choose when enabling the two electrics function.

now I do NEED A HERO, anyone?

I would check the towing harness is not faulty
http://www.ruleworks.co.uk/carguide/doc/towbar-wiring.pdf

Hope this helps 2008 xs
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