Technical towbars
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Technical towbars
Fitted one myself to 1.9 Diesel 16V.
Fairly straight forward job but is a little time consuming. The rear bumper has to come off and you have to lower the back end of the exhaust. Also a small piece of bumper has to be cut out from the UNDERSIDE of the bumper and is not visible if done carefully.
As for reversing sensor then the tow bar I fitted does not trigger them even with the removable "swan neck" ball left attached. However they will trigger with trailor/caravan attached.
The Croma will accept a plugin towing electrics module that should? turn the sensors off when a trailor is plugged but I think it is expensive. This kit does not cater for caravan aux. electrics either.
Fairly straight forward job but is a little time consuming. The rear bumper has to come off and you have to lower the back end of the exhaust. Also a small piece of bumper has to be cut out from the UNDERSIDE of the bumper and is not visible if done carefully.
As for reversing sensor then the tow bar I fitted does not trigger them even with the removable "swan neck" ball left attached. However they will trigger with trailor/caravan attached.
The Croma will accept a plugin towing electrics module that should? turn the sensors off when a trailor is plugged but I think it is expensive. This kit does not cater for caravan aux. electrics either.
any more advice on this any others fitted? do you need to use a 7 WAY BYPASS RELAY?
where does the plug go if you get a detachable ball type?
where does the plug go if you get a detachable ball type?
Usually next to the towbar mounting part under the car.
If you use a manufacturer specif interface module which is designed to plug directly into the Croma wiring system the I believe this is all you need for the lights.
However these units are a) rare and b) very expensive.
On all modern cars one should ALWAYS use the seven way bypass control unit. These also have the manditory audio repeater for the indicator lights.
Next year (I think it is next year) tow bars and electrics become an MOT testable item so must comply with all the relevant regulations. If you don't have audio/visual safety repeater function then you will fail the MOT.
With my detachible towbar the electric socket is a single 13 Pin affair which swings/folds up and down. It pivots left/right folding leftwards up behind the bumper.
To fit towbar and electrics the rear bumper and lights have to come off and the back end of the exhaust has to be dropped. All holes required to be drilled (on my towbar) were straight forward vertical inline ones. No fancy right angle drill heads required.
Two things to do/watch out for:
1) make the 7 way relay feeds as far away as possible from the rear light units. This ensures that if you mess up or have other problems you are not compromising the wiring loom close to the light unit connectors. Arround central wheel arch area is a good place. Mistakes here can be easily corrected.
2) if you have a folding/swivel up/down socket then you need to plan for a nice large diameter loop/curve so that the wire does not twist in the back of the connector when the socket is rotated through 90 degrees.
Basically before starting the wiring have a dummy layout to check all component positions and cable runs.
The towbar I fitted was a Brink 4361
Brink have been purchased by Thule and the Brink brand is being dropped.
http://www.thuletowbars.com/upload/manuals/436170.pdf
However these units are a) rare and b) very expensive.
On all modern cars one should ALWAYS use the seven way bypass control unit. These also have the manditory audio repeater for the indicator lights.
Next year (I think it is next year) tow bars and electrics become an MOT testable item so must comply with all the relevant regulations. If you don't have audio/visual safety repeater function then you will fail the MOT.
With my detachible towbar the electric socket is a single 13 Pin affair which swings/folds up and down. It pivots left/right folding leftwards up behind the bumper.
To fit towbar and electrics the rear bumper and lights have to come off and the back end of the exhaust has to be dropped. All holes required to be drilled (on my towbar) were straight forward vertical inline ones. No fancy right angle drill heads required.
Two things to do/watch out for:
1) make the 7 way relay feeds as far away as possible from the rear light units. This ensures that if you mess up or have other problems you are not compromising the wiring loom close to the light unit connectors. Arround central wheel arch area is a good place. Mistakes here can be easily corrected.
2) if you have a folding/swivel up/down socket then you need to plan for a nice large diameter loop/curve so that the wire does not twist in the back of the connector when the socket is rotated through 90 degrees.
Basically before starting the wiring have a dummy layout to check all component positions and cable runs.
The towbar I fitted was a Brink 4361
Brink have been purchased by Thule and the Brink brand is being dropped.
http://www.thuletowbars.com/upload/manuals/436170.pdf
kadee
New member
Had mine fitted to my 1.9 8v by Tanfield Trailers in Horsham Sussex. Cost me £230.02 inc VAT in May 2009. It's listed as a Vauxhall Vectra Bar, price included all the Electrics and Electronics two sockets, Tow Ball and covers and took them half a day to fit, mind you they have got all the kit in their workshops. Give them a call on 01403 269100 they will answer any questions. I don't know where you are because they do also run a mobile fitting service.
i am a long way from them right the other side of Essex nearly in Suffolk, but thanks, if vectra is the same i may be able to find a used one to save a bit of money
i found this http://www.discount-towing.co.uk/home/pdf/213E.pdf it may be useful
so today i went to scrappy and a vectra C taxi had just arrived, it had this tow bar. that is now mine.
View attachment TV352.pdf
it also had this box in the boot hidden by the side panel that the tow bar electrics just plugged into ( the white label says trailer module, do our cromas have this or some thing like it i can swap it for this one and have it all just work?
View attachment TV352.pdf
it also had this box in the boot hidden by the side panel that the tow bar electrics just plugged into ( the white label says trailer module, do our cromas have this or some thing like it i can swap it for this one and have it all just work?
Attachments
what will happen if i dont have a bypass relay? if all i am going to get is bulb warnings and reverse sensors beeping i can live with that
When I asked at the time they told me that it was to do with protecting the ecu and the other electronics in the car due to the type of wiring or something. It was a long time ago 
It's also got a fuse fitted in line with it (no idea where it draws power from) and if I connect or disconnect the trailer board, trailer or caravan with the ignition on it blows the fuse. Just to be on the safe side I always take the key out the ignition and keep a bunch of fuses in the spare wheel well. The relay itself is mounted behind the boot trim at the small, square access panel on the passenger side which just pops off.
There's a post on the ukcampsite forum from someone asking about a buzzing problem with theirs and a couple of the replies go into a bit of detail about how the wiring works which might be useful. Mine had the same problem after not being used for ages and the good old switch it off, leave it for 5 and switch it back on again cured it.
www.ukcampsite.co.uk/chatter/display_topic_threads.asp?ForumID=31&TopicID=230987
It's also got a fuse fitted in line with it (no idea where it draws power from) and if I connect or disconnect the trailer board, trailer or caravan with the ignition on it blows the fuse. Just to be on the safe side I always take the key out the ignition and keep a bunch of fuses in the spare wheel well. The relay itself is mounted behind the boot trim at the small, square access panel on the passenger side which just pops off.
There's a post on the ukcampsite forum from someone asking about a buzzing problem with theirs and a couple of the replies go into a bit of detail about how the wiring works which might be useful. Mine had the same problem after not being used for ages and the good old switch it off, leave it for 5 and switch it back on again cured it.
www.ukcampsite.co.uk/chatter/display_topic_threads.asp?ForumID=31&TopicID=230987
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If your are not using a manufacturer specific interface module then you should (even say MUST) use a bypass relay unit.
The bypass relay unit does the following:
1) provide the legally required audible indicator signal that the trailer/caravan indicator is working and drawing current
2) power to the trailer/caravan lights is NOT taken from the cars individual lighting circuits but is provided by a separate fused power feed which is switched to the relevant trailer/caravan lights via relays that only take a few milliamps from the cars lighting circuits.
Not fitting a bypass relay unit can result in the following:
1) overload of existing vehicle wirings and/or body computer expected loads
2) no legal required audible and failure warnings
3) trailer/caravan wiring faults can damage the vehicles main wiring/systems
With more modern cars where cost have been cut to the bare minimum then the wire that feeds say the left rear indicator will be rated for 15W/1.25A (or less). On old cars this wire could support 5A or even 10A, or more. A simple tap/spur power connection into this circuit could have unseen damaging heating effects deep in side a mutli cabled and bundled loom.
Bypass relay (or manufacturer/OEM pucker control unit) is IMHO the only safe and sensible way to proceed.
The bypass relay unit does the following:
1) provide the legally required audible indicator signal that the trailer/caravan indicator is working and drawing current
2) power to the trailer/caravan lights is NOT taken from the cars individual lighting circuits but is provided by a separate fused power feed which is switched to the relevant trailer/caravan lights via relays that only take a few milliamps from the cars lighting circuits.
Not fitting a bypass relay unit can result in the following:
1) overload of existing vehicle wirings and/or body computer expected loads
2) no legal required audible and failure warnings
3) trailer/caravan wiring faults can damage the vehicles main wiring/systems
With more modern cars where cost have been cut to the bare minimum then the wire that feeds say the left rear indicator will be rated for 15W/1.25A (or less). On old cars this wire could support 5A or even 10A, or more. A simple tap/spur power connection into this circuit could have unseen damaging heating effects deep in side a mutli cabled and bundled loom.
Bypass relay (or manufacturer/OEM pucker control unit) is IMHO the only safe and sensible way to proceed.
this is sounding a lot harder than i thought it was going to be, i found a lot of things behind the side panels but i started a new thread for them, to find out what they are,
is this a good one? http://www.ebay.co.uk/itm/TOWING-7-WAY-BYPASS-RELAY-SMART-LOGIC-RELAY-NEW-/281128712971
seems to be half the price of other places for same model number, its a bit like the one Brian posted
seems to be half the price of other places for same model number, its a bit like the one Brian posted
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tarquin1867
Member
This is the type mine has had fitted when the towbar was fitted (commercially).
Only down side can see is it may be 2nd hand?
Only down side can see is it may be 2nd hand?
the seller has sold 58 and has 10 left though, so i dont reckon its 2nd hand, it might be like computer stuff and come with no retail box ment for trade use
These bypass relays are all very much a similar price wherever you get the from.
Ignoring price then you should/must ensure your to be supplied unit comes with fully wiring, tech data, etc.
A few pounds extra for a "complete package of hardware and docs" could/will save you a shed load of grief, lost time, etc.
Nick
Ignoring price then you should/must ensure your to be supplied unit comes with fully wiring, tech data, etc.
A few pounds extra for a "complete package of hardware and docs" could/will save you a shed load of grief, lost time, etc.
Nick
The relay didn't arrive today and I needed to pick up my new dolly, originally planned to pick it up in my sons work van as its his day off but he had to lend it to some one else who's van broke, so I towed the dolly with out lights but my car lights could clearly be seen over it and it has reflectors.:devil:
it looked a lot smaller in the ebay photos
it looked a lot smaller in the ebay photos
