Citroen C4 (2004 - ) - 09 1.6 Fitting a towbar - "Trailer Stability Progr

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Fri 29 Jan 2010 14:23
09 1.6 Fitting a towbar - "Trailer Stability Progr - BigJohnD
I'm looking to fit a towbar for a small caravan.

The Citroën dealer offers the full package of fitting the towball and electrics. I'm told the fitting includes reconfiguring the car's ESP so that when a trailer/caravan is present, the stability programme switches to trailer mode. However, this is expensive.

A local towbar specialist will to the job for a third of the price, but he tells he will fit a relay to by-pass the car's CANBus and everything will be fine.

Whom do I believe?

I assume Citroën have actually gone to the trouble of recognising that a car behaves differently when towing a 5m trailer weighing a tonne plus, and if/when the driver has to brake hard or swerve, have worked out the safest way for the the car to respond, which will different from when without a trailer. And consequently by-passing this safety feature is irresponsible and could upset insurers in event of a big claim.

Or is this just safety being taken to unnecessarily extreme levels, and all that's really needed is the towball and a link for the lighting?

I expect this applies to other cars with similar electronic stability programmes.

(BTW, it is not possible to permanently switch off the C4's ESP without serious tinkering.)
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Fri 29 Jan 2010 14:42
09 1.6 Fitting a towbar - "Trailer Stability Progr - WorkshopTech
You need software parameters chaning for the ESP to work properly with trailer, so the dealer is correct.
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Fri 29 Jan 2010 15:26
09 1.6 Fitting a towbar - "Trailer Stability Progr - BigJohnD
I thought that would be case. The independent was too dismissive of ESP for my liking.

I'll now be looking into some DIY to reduce the costs (£160 for the towball + £112 for the wiring kit) before getting the dealer to reconfigure things with his laptop.

Cheers.
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Fri 29 Jan 2010 16:09
09 1.6 Fitting a towbar - "Trailer Stability Progr - TheOilBurner
I went down the route of fitting a proper plug in wiring kit rather than a by-pass relay for the same reason.

I'm also a great believer of doing the job properly and not bodging it, which for me, wiring the towbar 12v feed directly to the battery (to avoid stealing voltage from the light circuits on CAN) is a major bodge! Even if it does save quite a few quid.

There's something very satisfying about pluging a module directly into the rear fuse box instead of fitting half a dozen snap connectors to otherwise unspoilt wiring!

Plus, it might, just might interfere with the Citroën economy mode system, so best to use the proper kit really. As a bonus, reversing sensors and bulb failure systems will work properly with the trailer too.
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Fri 29 Jan 2010 16:40
09 1.6 Fitting a towbar - "Trailer Stability Progr - BigJohnD
There's something very satisfying about pluging a module directly into the rear fuse box instead

> > of fitting half a dozen snap connectors to otherwise unspoilt wiring!
Plus it might just might interfere with the Citroën economy mode system so best to
use the proper kit really. As a bonus reversing sensors and bulb failure systems will
work properly with the trailer too.

>>
Clearly the purpose designed system is better all round, but let's not get diverted into benefits of Economy Mode!

bigjohnd.org.uk/C4/OtherPhotos/econmode.jpg

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Fri 29 Jan 2010 17:07
09 1.6 Fitting a towbar - "Trailer Stability Progr - TheOilBurner
LOL! What I meant was that with the by-pass relay drawing straight from the battery, it's plausible the Economy Mode might get confused and become even more infuriating!! :)
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Sat 30 Jan 2010 16:49
09 1.6 Fitting a towbar - "Trailer Stability Progr - BigJohnD
www.rightconnections.co.uk/tsp.swf

The above is a vid clip showing how TSP works, and should convince the by-pass boys of the risks they're taking.
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Sat 30 Jan 2010 17:53
09 1.6 Fitting a towbar - "Trailer Stability Progr - Simon
That is a very informative video. Thumbs up to BigJohnD.
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