Wiring Kits - Car coding / program / activation

[BaileyNiggles]

Got a second-hand car with, I believe, a dedicated wiring kit already fitted, but the parking sensors don't cut out when reversing, and I'm not sure the car's stability electronics are helping on any anti-snaking either. I believe its a dedicated kit as (i) the car's foglight does cut out correctly, (ii) there's one of those gibberish non-self-explanatory alien UFO language stickers on the boot lid that's supposed to tell service diagnostic staff that a kit is fitted and (iii) when rummaging under the boot trim for other purposes recently I didn't see any bodged cuts into the car's wiring.

When I fitted dedicated wiring kit to my other car I read or heard about the need to take it to a dealer to be coded / programmed / activated but didn't bother as it seemed to primarily concern parking sensors and as I didn't have any, and that car predated the trailer stability gizmos, so I didn't bother.

On the newer car I'd really like to be sure that all is as it should be.

My local Mercedes main dealer's service middleman chap, who fronts for the real service folk behind the scenes, didn't seem to know much about the subject so bluffed and rambled and generally didn't really inspire confidence that I'd be getting anything for my money.

I see Westfalia do a thing called Auto Code, so I could find a fitter with one of those, but I see their website says the tool "Covers most towing functions" ... so that doesn't sound foolproof either.

Has anyone ever had this work done? How much? How successful? Where done?

 

[DaveA1]

I fitted my kit myself, surprisingly simple. I got all the information I needed from were I purchased the wiring loom from. If you go onto PHJones web site and put your reg in it will tell you all you need. At least you will know what the wiring should do. Are you sure that it's a dedicated kit and not a bypass relay type that controls some functions and not others.

My Insignia didn't need reprogramming, so made it easier.

 

[BaileyNiggles]

Yes, I 'd agree as regards the one I fitted. The blurb and some fitters bamboozle people into paying more for having what is in fact Lego-like childsplay. But sounds, as regards the car that needs coding, "into the great unknown mystery, I go first, Indy" ...

 

[CustardAvenger]

I had a Volvo dealer retrofit the detachable towbar to my used XC60. As it was the official Volvo part the elecrics module seemed to work fine; parking sensors were disabled etc. What I didn't know was if the fridge would be powered. I had used the car to tow for about a year with a caravan with no fixed fridge, but I had read they did not enable the fridge pin by default.

When the car was in for service, I asked them to confirm if the pin for powering the fridge was live, but when the service manager called, he went off on a tangent saying I needed an adapter to power the fridge. I couldn't seem to explain, that the caravan had a 13pin plug which directly connected to the cars socket... no adapter existed which would be relevant. In the end, he agreed to get the service engineer to call. He simply said yes, the fridge will be powered. I have no idea how that got lost in translation!

 

[BaileyNiggles]

Battery charging and fridge connections and whether they even do anything on the caravan if present at the car, are of a similar unfathomable mystery level as erm, er.... no actually that's a mystery level all on its own. Might help if the Bailey instruction book spent less time bombarding the pages with repeated senseless warning messages along lines of do not stand naked on the roof in a thunder storm, or passing a crude block diagram off as a "circuit diagram", and focussed on instructional facts..

 

[xtrailman]

Its not difficult to establish if your car 13pin is fully wired.
A check at the cars socket would establish that, the fridge has a separate supply as the permanent supply does.
If you don't feel confident or lack a voltmeter then you can buy a plug in checker.

I have bypass electrics on mine I fitted the latest one as I transferred it from my last car. So no sensor cut out, however I do have a switch on the dash to turn them on or off....

As for the fog switching off a standard bypass system can be fitted with a cut off switch in the 13pin socket, so the fact it cuts off does not confirm a dedicated system is in place.

 

[BaileyNiggles]

Knowing what the caravan should or shouldn't do with a constant 12V supply seems the harder part. Master Switch on or off, for example? Bailey manual woeful on that sort of thing. I'd concede I need perhaps test battery voltage whilst someone revs engine a little, and likewise spend more time experimenting with fridge.

Interesting observation about fog light cut off. I really need pull the car boot lining out and cross reference what I see with a wiring kit instructions.

Thanks

 

[xtrailman]

Master off while towing.
Permanent supply feeds the ATC and battery charging.
Fridge supply is required for battery charging as it operates some relays inside the caravan, one of which allows caravan battery charging only when the fridge supply is evident, the fridge supply should ideally only be present with a running engine.

You can buy a cheap plug in voltmeter which fits into your car or caravan socket, cost about £2 on Amazon.

 

[BaileyNiggles]

To answer or put a note against my own question, I went to a local independent Mercedes garage ... Richard Hollings / RH Auto Services in York and the trailer 'coding' thing was a simple flick of a on-screen switch on his plug in gizmo that is generally used for servicing anyway. A doddle. No charge as was in for service. Very helpful and very painless. Shame Mercedes dealers proper are so vague and expensive and fail to inspire confidence.

 

[CustardAvenger]

To answer or put a note against my own question, I went to a local independent Mercedes garage ... Richard Hollings / RH Auto Services in York and the trailer 'coding' thing was a simple flick of a on-screen switch on his plug in gizmo that is generally used for servicing anyway. A doddle. No charge as was in for service. Very helpful and very painless. Shame Mercedes dealers proper are so vague and expensive and fail to inspire confidence.

So many things on cars are now software controlled. Want to buy the 120BHP or 150BHP engine? That's a £3000 option, but in reality it is a engine management re-map.

My Volvo dealer quoted me £500 to replace rear brake pads (i'm not sure if that included the discs) I declined; but without the correct device my mechanic already had, which could connect to the ECU and set the rear electronic parking brake into maintenance mode, I would had to have paid it. No wonder Mercedes are cagey about revealing their electronic options, as the mark-up is huge.

 

[Anseo]

To answer or put a note against my own question, I went to a local independent Mercedes garage ... Richard Hollings / RH Auto Services in York and the trailer 'coding' thing was a simple flick of a on-screen switch on his plug in gizmo that is generally used for servicing anyway. A doddle. No charge as was in for service. Very helpful and very painless. Shame Mercedes dealers proper are so vague and expensive and fail to inspire confidence.

So many things on cars are now software controlled. Want to buy the 120BHP or 150BHP engine? That's a £3000 option, but in reality it is a engine management re-map.

My Volvo dealer quoted me £500 to replace rear brake pads (i'm not sure if that included the discs) I declined; but without the correct device my mechanic already had, which could connect to the ECU and set the rear electronic parking brake into maintenance mode, I would had to have paid it. No wonder Mercedes are cagey about revealing their electronic options, as the mark-up is huge.

Apologies for detracting, but Custard Avenger makes a very relevant point.

I recently invested in Mercedes WIS (etc.) software and OBD 2 devices (I now have 3 hmy: ).

My wife drives a Mercedes A160 and me a Merc 220 diesel estate, so I thought the relatively small small investment worthwhile.

Pretty much all gobbleydook it was initially, but, I am slowly coming to terms with it all and have carried out works such as EGR replacement, Exhaust Gas Recirculator Sensor and am about to remedy or replace components related to Air Flow Mass sensor on my wife's car, I've saved more than a few bob so far.

I hope I don't need to delve into the wizardry and complications of my own car (it will go wrong- I know hmy: ).

Learning curve is huge (for me) but I will continue to learn, unfortunately the 'tech' will put many things outwith the comfort Zone of my pocket. :dry:

 

[Woodentop]

With a Bailey and 13-pin electrics it is very easy to find out if the fridge/charging wiring is present and working.
Switch the caravan master on and read the voltmeter.
Plug into the car - if ATC is fitted then the system will be heard to activate and the red LED will light. Read the voltmeter again - it will likely be a little lower than before.
Start the car engine. NOTHING powered by 12V in the caravan including the meter should work - period. If it does then fridge wiring is not present and the voltmeter will be reading higher than before.
The habitation relay - which stops caravan electrics working - overrides the effect of the master switch so it matters not whether it is on or off. However if the caravan is going to be static with the car connected for a long time - as on a ferry - then it is a good idea to put the master off . If it is a long crossing and especially if the caravan has ATC it is even a good idea to disconnect the 13pin to prevent the ATC chuntering due to the ship's movements and avoid a flat (car) battery at the other end.