Technical towbar on a 500C twin-air and electrics

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Technical towbar on a 500C twin-air and electrics

penguin

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Just fitted the wesfalia towbar on the wife's 500C twin-air - went a lot easier than the instructions indicated as it is NOT necessary to remove the bumper - just undo the two screws underneath to slide the bar through. And there isn't any mucking around with the exhaust and heat shields as the twin-air final silencer box is so small compared to the others.

Electrics are a bit more of a problem - the wiring loom colours don't seem to match anything shown in other threads, but I think they are:
left:
1 - Blue+white - indicator
2 - Grey+green - reverse
3 - Black - ground
4 - Green+white - brake
5 - Yellow+red - sidelight
right:
1 - Yellow+black - sidelight
2 - Green+yellow - brake
3 - Black - ground
4 - Brown+grey - fog
5 - Blue+black - indicator

If someone could verify these, I'd be very grateful.

Also, the handbook shows that Fuse F09 under the bonnet is labeled "trailer" - there isn't a fuse in the slot, but does this mean that there is a feed from the fuse box into the boot area already? The (westfalia) instructions tell me to add a new wire and in-line fuse holder onto the battery and run a new wire all the way through the passenger compartment to the boot to power the by-pass relay box, which is a bit of a palaver and a lot of wasted effort if I subsequently find there is already a feed hidden in the loom somewhere! So does someone have a wiring diagram for the 500c twinair that they could check this for me?

Thanks.

del - somewhere in somerset.
 
Hi Penguin, just a quick question. Is the tow ball hitch assembly removable?

Only asking as I used to get problems on some cars with parking sensors fitted, they would beep all the time when reversing as the inner sensors assumed the ball to be an object in the way.

Good luck with the wiring. (y)
 
yes - had that problem with my Passat, so we went for the fully detachable one for the 500c - and you really can't see anything of it when its removed, even the electric socket folds up behind the bumper.
 
Is it a Westfalia towbar you have?

fitting instructions for the towbar are here
http://www.westfalia-automotive.de/fileadmin/templates/pdf/306-fiat/a306311691101.pdf

and the fitting instructions for the wiring kit is here.
http://www.westfalia-automotive.de/fileadmin/templates/pdf/e_anlagen/306/e306560391101-002.pdf

I have the Westfalia wiring on my Caravelle. Great stuff, keeps the warranty with no issues, puts the ESP into towing mode and even shows a trailer hooked up on the screen when the reverse sensors activate.
 
err.. yes, thanks, but I've already got those, they really aren't of much help as they assume that you have the additional wiring loom and are for a 500 not a 500c. And they don't list the wiring colours for the car....

I was trying to avoid ripping all the trim off the car just to put a power feed through - especially as the Fiat Handbook lists fuse FS09 as "trailer" which would imply that they have already done it for me.... in which case, where does it appear in the boot space?
 
Interesting as I brought a towbar from wesfalia (far cheaper than Fiat and it's 100% the same ) and the electrics from Fiat (which is by wesfalia but is to Fiat spec for the garages to fit and has a FULL loom and the relays and more included) but in addition has a loom that goes to the front of the car to pick the power up as there doesn't seem to be one already laid by Fiat plus instructions to bypass the reversing sensors.

The Fiat "wesfalia" electric instructions shows pictures of the trim all pulled out to get the loom in.

Interesting you don't need to take the bumper off to fit it to a Twinair ,as that's exactly what I will be doing , once I have put a few miles on the car as its only 2 weeks old .
 
err.. yes, thanks, but I've already got those, they really aren't of much help as they assume that you have the additional wiring loom and are for a 500 not a 500c. And they don't list the wiring colours for the car....

I find sometimes others reading threads like this find links to instructions etc very helpful, as it's not just the OP that reads the replies.
 
I find sometimes others reading threads like this find links to instructions etc very helpful, as it's not just the OP that reads the replies.

I have no plans 'for the moment' to fit a towbar but did find the links useful.(y)

The 500c comes with rear parking sensors as standard whilst with the standard 500 it has to be specified as an optional extra.
It would appear that Westfalia didn't take account of the differences since the additional wiring for the sensors means that you may not have to wire back as far as the battery.
I have the rear parking sensors on the current motor so I would be interested on the outcome of this thread given the similarity of the wiring logic across the 'Fiat' range.
Remembering another thread of retrofitting fog lamps it would also be an example of where one could legitimately wire as set of fog lights at the front if they were not already fitted if they were 'approved' along the same lines as Wesfalia.
 
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Well, having spent another hour peering at the 500c, it looks to me that the fuse 09 doesn't actually have any connection to it, so labelling it "trailer" in the handbook doesn't seem to be overly helpful - I guess if you have the work done at the dealer, they put the connector inserts in and so make it functional.

The Westfalia instructions have a note about adding another connection to disable the reversing sensors when the trailer is attached - to be honest, I'm not sure I understand what they mean, but obviously, they must have thought about it at least... As I have the removable hitch, I'm not too bothered, ok, so the sensors will beep away when I'm reversing with the trailer on the back, but I can live with that. Most of the time the hitch will live in its bag in the boot, so the sensors are not affected.

Sorry, I may have been a little grumpy in my response to deeyup, my excuse was that I was getting a bit frustrated - would be be an idea to move the files into the download area so everyone can see them?

So, how does everyone else that has fitted a towbar run the cable through from the battery, my wife is really, really unhappy about me ripping out the trim, she went white when I showed her the westfalia instructions.....
 
Well, having spent another hour peering at the 500c, it looks to me that the fuse 09 doesn't actually have any connection to it, so labelling it "trailer" in the handbook doesn't seem to be overly helpful - I guess if you have the work done at the dealer, they put the connector inserts in and so make it functional.

The Westfalia instructions have a note about adding another connection to disable the reversing sensors when the trailer is attached - to be honest, I'm not sure I understand what they mean, but obviously, they must have thought about it at least... As I have the removable hitch, I'm not too bothered, ok, so the sensors will beep away when I'm reversing with the trailer on the back, but I can live with that. Most of the time the hitch will live in its bag in the boot, so the sensors are not affected.

Sorry, I may have been a little grumpy in my response to deeyup, my excuse was that I was getting a bit frustrated - would be be an idea to move the files into the download area so everyone can see them?

So, how does everyone else that has fitted a towbar run the cable through from the battery, my wife is really, really unhappy about me ripping out the trim, she went white when I showed her the westfalia instructions.....

When I looked at the diagrams for getting a 'good' feed from the battery it looked a bit daunting. If it is done correctly you would never know it was done. Often keeping someone in the dark has it's advantages.;)
 
So, how does everyone else that has fitted a towbar run the cable through from the battery, my wife is really, really unhappy about me ripping out the trim, she went white when I showed her the westfalia instructions.....

Over the years (but a few years back now) I fit or had fit several tow bars to various cars and they normally required at least one wire to be run to the front.

The only exception to this was a Land Rover Discovery which being a vehicle virtually designed to tow had all the connections made behind the rear lamp clusters - no trim dismantling required.

All the others have required a degree of trim removal if the wire is to remain out of sight but also out of harms way where it could be caught or snagged by vehicle occupants.

Occasionally (don't know if this applies to a 500) you can be lucky and get away with pushing the wire up behind the plastic sill covers, inner panels and the like but that is unusual and I think from memory I only ever achieved this on a XR3i.

Your other challenge is to get the wire through the bulkhead - normally you can sneak it through a hole used by another wire/component (checking of course it can't chafe)

So I think you are going to have to accept a degree of dismantling unless you can do as suggested above.

Good luck -

PS I'm following this thread with interest as I'm toying with the idea of a Tow Bar for our 500 to cope with a reduced carrying capacity and runs to the local tip.
 
Can I recommend someone to help you out?
http://www.britanniabristol.co.uk/ They are Westfalia distributors/dealers

We fitted the Caravelle wiring ourselves (VW allotted 3.5 hours work for this) mostly. There was only a few connections left to be made at the light switch and the fuse board near gear stick. Coding was then required.

Britannia were more than happy to just do the final work including coding (which is not needed on Fiat 500) at their hourly rate which at the time last year was about £40.
They are in Bristol so hopefully not too far from you?

I'm sure they would be happy to advise you over the phone too if you don't want to go there.
 
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Getting the wire from front to back will be fairly easy once the boot carpet is out (see 500 boot light thread) use a bamboo garden cane from the passenger side kick plate. And fish/ draw the wire through

Check the gp guides section.for my tow bar wiring guide I would spur off the dashboard fuse box supply as in guide
 
Getting the wire from front to back will be fairly easy once the boot carpet is out (see 500 boot light thread) use a bamboo garden cane from the passenger side kick plate. And fish/ draw the wire through

Check the gp guides section.for my tow bar wiring guide I would spur off the dashboard fuse box supply as in guide

could you post the link? not sure I understand where to insert the cane...

taking a feed from the dashboard fuse box would solve the problem of how to get the wire from the battery and into the passenger compartment - even by following other cables, I can't see an easy way of doing it... so how do you get at the dashboard fusebox then?
 
thanks - the third link was the most useful with the picture of the new fuse by the under-dash fuse box - can you recall what colour the feed wire was?
 
thats on a Grande punto.. If you look under the passenger foot well you will see the loom that goes into the fuse box/ body computer i think its the biggest thick black wire that goes into the base (need a multimeter to check but think my sister will murder me if i pull her 500 apart)
 
Well, it's all done and working fine - thanks to everyone who made suggestions.

So, for anyone else that wants to have a go, here's how I did it (remember that this is on a 500c twinair, so may not be appropriate for other models).

Don't take the bumper off, just remove the two screws underneath.
The two longer covers on the chassis rails inside the boot have to be punched out - I used a screwdriver - to get the two retained nuts into position. these are tricky and required a lot of effort to tighten up and there is very little clearance around them in the chassis rail. They do make a useful place to bring the electrics cable up into the boot area without having to drill any holes anywhere. I routed mine to the left rail, on reflection, it might have been better to use the right hand one instead as it keeps the cable further away from the exhaust, but there is at least 6 inch gap on the twinair, so I don't think it will be aproblem.
Strangely, no shake-proof washers or nyloc-nuts were provided in the kit, and there is not a lot of room to swing a torque wrench....
Wiring was fairly easy in the end, I routed the cables from the right cluster around the top of the boot opening, underneath the trim, and fixed the realy to the bracing bar on the left. Actually making the connections into the loom was fiddly and involved lying on my back with the rear seats down and my feet by the windscreen...
The power feed to the realy also turned out to be surprisingly simple. If you take the cover off the dashboard fusebox in the parcel tray in front of the passenger, you can just see the big red feed wire coming in from the bottom. I idenified the wire by wrigggling each one of the bundles underneath and then sripped back the black woven cladding about 2 inches under the parcel shelf. The kit includes a big scotch-block connector for this, but it was a disaster, so I ended up stripping the wire (very carefully with an insulated handle knife - don't want to short the feed out on the bodywork!) and soldering on my wire. Now wrapped up in black insulating tape, it is barely visible. I also taped the in-line fuse holder under the fusebox surround (which meant another trip to Halfords, as the kit didn't include a fuse...). The feed wire ran neatly under the trim panel that covers the inner sill (cill?) which is secured by a srew near the seatbelt anchorage and then pops off vertically.

So my verdict is:
Don't exactly ignore the instructions, but they do massively over-complicate the procedure. If they hadn't frightened the daylights out of me, I'm sure that I'd have done the job just as well, but in half the time. Knowing what I do now, I reckon the bar can be fitted in about 40 minutes and the wiring in another 40 minutes - most of the time is spent identifying the right wires....
 
Hi, I am a newbie having only owned - well the Wife has only owned her 500 for four days. It's only a 1.2 pop. I have got a tow bar and set of eletrics from a previous car in the garage. Can I ask why you need to run a live wire to the trailer electrics? Never had to do this before on any other cars I've fitted towbars to. Also is it permanent live or just ignition live? Thanks
 
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