I have noticed a problem with my tow ball mounted bike carrier.

I thought it was the bulbs in the carrier - some numpty parked too close and cracked both lenses so I thought cold water and hot bulb = blown bulb. Indeed on investigation they both were blown but replacements have not solved the problem.

So, I got my trusty multimeter out and have determined (I think!) that I have no power coming from the car's 13 pin electrics to the two pins that make the tail light circuits.

My question is does the RR have a separate fuse panel for the towing electrics and if so would it fuse each trailer circuit individually as the rest of the lights work as they should?

Seems a bit odd for both tail light circuits to fail at the same time unless the bulbs blowing caused the fuse(s) to go too?

2011 MY with factory towbar.

Any thoughts of where to prod around before I get an auto sparks in? Bish.

2005 110 TD5 CSW
2011 TDV8 Vogue SE (gone)

Try the rear junction box fuse 8R and relay 3R. I think you can change the relay for one of the others to check operation.

The WM is in the Wiki if it helps.

And also check the wiring of the tsilerboard/cycle carrier. It may damaged unseen Cheers
Richard

(there are no such things as an ordinary FullFat, an ordinary cat or too many tools)
2011 TDV8 Vogue Santorini Black
Gap IIDBT

Sorry for the delay in replying - finally got some post Christmas headspace to investigate.

Sadly F8 is fine and I have swapped R3 for another one with no change.


Any more ideas please? WSM seems to be rubbish on towing electrics. Bish.

2005 110 TD5 CSW
2011 TDV8 Vogue SE (gone)

Hi Bish

Discconnect the fitting in the spare wheel well and see of the wires corresponding to the lamp wiring in the trailer supply socket on the car are giving a correct reading, if you follow me. That will tell you if the car is supplying the power or that the wiring loom to the car socket is faulty. This assumes the car was specified with a tow prep when ordered.

You can tell that if the car has a grey socket with 13? connections in the spare wheel well, NS rear of the well. Cheers
Richard

(there are no such things as an ordinary FullFat, an ordinary cat or too many tools)
2011 TDV8 Vogue Santorini Black
Gap IIDBT

left and right tail lights are fed from separate pins therefore a failure of both together is unlikely
Have you check the earth?

any update on this
mine has the same problem
bong of doom, check trailer lamp=
no side lights on trailer but indicators/stop lamps working fine
13 pin towing electrics
all fuses appear fine

Not yet - hope to get some time over the weekend to prod about as rjff suggests....

I don't have any warning messages though...... Bish.

2005 110 TD5 CSW
2011 TDV8 Vogue SE (gone)

Bish

I'd also go with checking the earths and if you have access to another trailer/light board/cycle carrier check using that. And check your carrier on another vehicle with known working lights. Cheers
Richard

(there are no such things as an ordinary FullFat, an ordinary cat or too many tools)
2011 TDV8 Vogue Santorini Black
Gap IIDBT

It is definitely the car - I have put the rack on a friends disco 4 and all worked as it should. I have also tried another 13 to 7 pin adaptor and had the same symptoms.


Hopefully I'll get some time at he weekend to try everyone's suggestions.

Thanks for the input! Bish.

2005 110 TD5 CSW
2011 TDV8 Vogue SE (gone)

ok
trailer tail lamps have packed up
all other trailer lights work ,indecators,stop lamps ect

done a bit of testing and this is what i have done/ found

1 ive checked fuse 17 in boot(fuse is ok ) and checked there is 12V at trailer ECU plug, red/white wire,this is the main permanant feed to trailer ECU

2 then turned lights on and checked i have 12V in the slate/white whire at ECU plug ,this is the feed from the light switch to the L/H trailer tail light (all good so far)

3 then checked slate/black wire out of the ECU that feeds pin 7 in the trailer plug 0v on that wire

4 done the same for the R/H trailer curcuit ,slate/purple into ECU 12V

5 0V out of ECU on slate/red to pin 5 of trailer plug

6 disconected ECU then put a 3amp fused jumper between slate and white wire and slate and black L/H trailer light is now working

7 done the same with slate and purple and slate and red ,R/H trailer ls also working

so looks to me like trailer ECU is knackerd

orderd one just waiting for it to arrive, ill let you know if it sorts it

was just going to bridge the termenals out inside the ECU if i need to tow before it arrives

mine is a 2005 loom so some of the wiring colours did not corrispond to diagram below (wires out of ECU to trailer plug was different)that was confusing to start with

bishbosh10 wrote:

Not yet - hope to get some time over the weekend to prod about as rjff suggests....

I don't have any warning messages though......

Happy days new ECU has sorted it
Now got sidelights again

well done - how much was the ECU ?

35 quid second hand off flebay
95 brand new

Today's update -

Disconnected the multiplug in the boot and checked the pins on that. They give exactly the same results as the trailer socket itself so the problem is definitely upstream of the multiplug.

Any more clues? Bish.

2005 110 TD5 CSW
2011 TDV8 Vogue SE (gone)