Trailer brake lights will not work - tried 4 other Grenadiers and all the same!

[landmannnn]

Testing 13 pin sockets is a mandatory part of MOT test. Test centres are encouraged to have an approved tester, although I believe a trailer board is acceptable.

 

[Tonyh]

Dealer has reported it to Ineos.
The MOT tool used showed a fail, not sure what it was recording but the Dealer showed me the fail whilst demonstrating on my car.
Dealer shared that all off the Grenadiers subsequently tested also failed the test!
Hopefully this is sorted soon.

 

[Tonyh]

Sounds like Ineos have roughly 2 years to fix it before they have an embarrassing situation on their hands in that case, at least in the UK. Is it safe to assume your dealer reported the finding back to Ineos?

What exactly would not be up to the MOT pass mark? The available power on the trailer circuit? Seems a bit obscure given that it works fine for LED light boards. I suspect most MOT test centres wouldn't bother checking it, unless it became common knowledge and they wanted some sport

Not sure abt MOT pass mark, was just told it would fail an MOT.
Whilst lights do work with LED installed, the brake light circuit that is, all the rest of the lights work fine.
It has to have something to do with the brake light module.
Dealer has reported to Ineos so hopefully a fix will be released soon.

 

[OzyGrenie]

I get a ‘trailer light error’ when my headlights are on but all the trailer lights work as they should. I had the Grenadier and trailer in at the Stirling Trailer Centre (who conveniently are a Grenadier service centre) and they think it’s something to do with the way the trailer fog light is wired which isn’t recognised by the car. As all appears to work fine I left it at that. Perhaps not very helpful for you but the wiring does seem to be quite sensitive compared to other vehicles. Very frustrating if the break lights aren’t working - sounds like an issue your dealer needs to get to the bottom of.

You need a resistor to be added to one wire to tail lights, it's very simply fixed. I had an auto electrician do it as is common knowledge.

 

[Tonyh]

You need a resistor to be added to one wire to tail lights, it's very simply fixed. I had an auto electrician do it as is common knowledge.

So how do you tow other trailers?
There is a fault as far as I am told with all Grenadiers so carrying a resistor isn’t a fix.
Changed the lamps to LED which has given a temporary fix just for my trailer, still cannot tow any others.