ML towbar electrics

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Piff

MB Enthusiast
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Feb 24, 2005
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Location
Suffolk
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Porsche Macan S
For my new car (2003 ML270CDi) I'm looking to fit a tow bar. My car electrics experience is limited to fitting radio/cassettes, etc. in the days when Hillman Hunters & Cortinas were popular:eek:

I've looked at many web sites for supply of towbars & electrics. There are simple cheap electric kits which are spliced onto existing wires but there are also dedicated wiring kits which plug into existing connector blocks on the car. These suppliers also advise that ther cars elecrtics may need upgrading to enable all features. As the car has Parktronic, I assume that the upgrade would be necessary. How much does a dealer charge for this type of upgrade?
My problem is that these dedicated kits seem to vary in price from £32 to £85.
Are some better than others? What would an MB dedicated electrics system cost?
 
I would personally always go for 'official' towing electrics, wherever possible. They should fully integrate with your vehicle's systems ... for example you'll get the 'trailer indicator' light on the dash flashing, rather than a buzzer in the boot sounding. Also the car's rear foglights should be disabled when you have something hitched up to the towbar, ditto for rear parktronic sensors, bulb failure circuitry still working properly, etc.

Is your car under warranty (e.g. approved used) btw? If it is and you get any electrical gremlins then having a non-OEM towing kit fitted might be an issue.
 
If I remember right, for one ML at least the tow bar wiring asked for a new rear SAM too. I wonder if it was a costs saving or why did they put a SAM that would not support the tow bar wiring. It might be expensive if this was the case.
 
Part no for wiring loom is B66850071 Retail £70.32 inc vat. The car may need to go to a MB workshop too though. You might have to put a different rear SAM on the car or it may just need a bit of coding to tell the car the towbar kit has been fitted.(depending on which SAM is fitted)
 
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As I have mentioned on another thread,

Mine, fully removable with twin elctrics, relays, bypass fitted at my home was £300 with a guarantee and free check up.

If your not happy fitting then I'm guessing your looking aroung £200 for your bar and bits?

So £100 extra for someone to fit is well worth it, if you start popping dashboard bulbs / short wires etc it could get pricey :(
 
Part no for wiring loom is B66850071 Retail £70.32 inc vat. The car may need to go to a MB workshop too though. You might have to put a different rear SAM on the car or it may just need a bit of coding to tell the car the towbar kit has been fitted.(depending on which SAM is fitted)

To give you an idea of how this is fitted: -

a) My Dec 2001 ML did not need a new SAM - so I would imagine as long as its later than they definetly no need for the SAM

b) he Mercedes wiring loom was very easy to install, you just take bumper off (about 4 bolts), screw connector onto premade holes by towbar, run wiring in through hole in passenger side at rear, and connect it up to a pre-existing connector. The most difficult thing was removing the airvent behind left hand side of bumber to plug the connector in (have to be careful otherwise clip breaks and then you need some sticky stuff after that)

When putting bumper back on, have to make sure its aligned or it will rub on the boot lid and lose its paint.

c) No coding needed, the MB trailer socket has a switch built in, so the SAM knows if there is something plugged in and knows that it has to adjust it's 'bulb failure detection' accordingly

R
 
Part no for wiring loom is B66850071 Retail £70.32 inc vat. The car may need to go to a MB workshop too though. You might have to put a different rear SAM on the car or it may just need a bit of coding to tell the car the towbar kit has been fitted.(depending on which SAM is fitted)

In addition to wiring loom, presumably I would need 13 pin socket, and any other parts?
 
Loom comes with the European towing socket . (cant remember how many pins)

- You need an adapter to make it into the UK variant - I got my adapter from halfords !

[edit: no other parts needed]

Cheers

Richard
 
Loom comes with the European towing socket . (cant remember how many pins)

- You need an adapter to make it into the UK variant - I got my adapter from halfords !

13 pins.

You can get 12N adapters (which simply go into the 13 pin socket and directly take the 12N plug), and dual adapters (which have 12N and 12S sockets on short flyleads). Or you can simply change your trailer to a 13 pin plug, which is neater.
 
13 pins.

You can get 12N adapters (which simply go into the 13 pin socket and directly take the 12N plug), and dual adapters (which have 12N and 12S sockets on short flyleads). Or you can simply change your trailer to a 13 pin plug, which is neater.

The trailer I'm looking at is German & has a 13 pin plug. The proper mb loom seems to be the way to go for the electrics.

Now I have to make a decision on the towbar type - options seem to be
Cheap & chearfull flange type which woould take a ball & pin set up and a bumper protector, cost around £125 for bar, ball/pin & bumper protector
Fixed swan neck (Westfalia or Bosal), cost around £100
Removable swan neck (Westfalia), cost around £220

Unless Partsspecialist can help with prices & part numbers for proper MB item?
 
Westfalia detachable for me :)

Looks neater imho , saves you catching you leg on it when filling boot and YOU will... Even when I leave mine on after towing I've caught my leg and it hurts :(

Your choice I appreciate.
 
FWIW the factory option removable towbar on my Vito is a Westfalia one. The one on my VW Sharan was too.
 
Westfalia detachable for me :)

Looks neater imho , saves you catching you leg on it when filling boot and YOU will... Even when I leave mine on after towing I've caught my leg and it hurts :(

Your choice I appreciate.


Picked up the car on Saturday - very pleased so far - only a couple of minor points that should have been picked up in the MB main dealer check (1 interior light bulb out & 1 rear numberplate bulb out)

I have checked behind the removable bumper panel & there is no tow bar fitted.
So, I've booked it in for a Westfalia removable & dedicated 13 pin wiring.
I jus hope that I don't need it so often that I get p****d off continually removing & refitting:)
 
Good choice! Fitting/removing the towbar only takes seconds (less time than unclipping the cover panel) :)
 
I jus hope that I don't need it so often that I get p****d off continually removing & refitting:)

If you would, you could always leave it there, the removable one does not have to be taken out except that you may want it to avoid gathering rust.

I'm sure you would find out removing the tow bar after use even if you did use it often. At least I do it on the car with the hook and others already seem to report the same.
 
Piff
Just consider the proper Mercedes ORIS kit. I say this having fitted a fixed towbar to my last W163 ML. The ORIS kit will stow away nicely behind the CD changer, the Westfalia doesnt quite fit.


Richard
 
Good point from Richard the Westfalia doesn't fit behind the multichanger!!

I leave mine on the car all year round. I used to remove it for the winter, but after the car had been valetted I notice the key had gone from the ashtray. Would have been no problem, but I couldn't find the spare either.

Spoke to Westfalia yesterday at the NEC and it seems they'll post a set of master keys which I can try in turn to work out which key fits, and then use the key code to order a new set. The keys cost about £20, plus secure P&P for sending the masters back and forth.

So the top tip of the day is... don't lose the key!!
 
Piff
Just consider the proper Mercedes ORIS kit. I say this having fitted a fixed towbar to my last W163 ML. The ORIS kit will stow away nicely behind the CD changer, the Westfalia doesnt quite fit.


Richard

Thanks, but I ordered the westfalia before I saw your post:(

I will have to find a bag/box to keep it in in the "footwell" behind the rear seats (I don't have the family pack 7 seat option)
 
Holy Thread Revival Batman! :bannana:

I have a fixed swan neck that seems to be secured by bolts - is there any reason I can't just take it off when needed and pop it back on when required? Guessing that there will be a torque requirement, but beyond that?
 
Holy Thread Revival Batman! :bannana:

I have a fixed swan neck that seems to be secured by bolts - is there any reason I can't just take it off when needed and pop it back on when required? Guessing that there will be a torque requirement, but beyond that?

It's a pain in the ****, would be my only suggestion....
 

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