207SW 2009 Towbar Electrical Fault

[AndyThomson]

Morning all,

Got myself a 207SW on Monday, a halfords lighting board on Tuesday & now it's Wednesday I've put them together and....nothing.

My electrical prowess has never progressed much further than regarding it as unreliable magic in a box, so despite having a multimeter to hand that's about as far as I can get for diagnosing faults. The manual seems pretty lacking in references to towbar electrics (aka all I can find is a single box to the tune of "make sure the lights work") & the headings in the Haynes manual make me think it won't be too much help either.

My leading guess right now is the dirt in the connection is the issue, but would appreciate any & all suggestions for other things it could be.

Many thanks,

Andy

[GiveMeABreak]

You need to make sure whatever it is you are hooking up to the vehicle electronics is compatible. Modern vehicle electrics have CAN networks and anything attached to CAN wiring must be CAN compatible.

Electrics for Towbar wiring for example should be independently fused and interface with the on-board electrical architecture of the vehicle. Most of the systems PSA sell are vehicle specific and include a trailer fusebox that is designed to integrate into the electrical architecture of the vehicle and protect the sensitive systems.

[AndyThomson]

Hi Marc,

Thanks for the quick reply. It's a 7-pin lighting board going into the OEM (presumably fitted from factory) 7-pin connection on the towbar, so I would not have thought compatibility would be an issue. If it is likely, do you know how I would go about confirming?

Andy

[GiveMeABreak]

I can't tell you from here on a Forum what has been fitted of course, nor whether it was a factory fitted or official accessory sorry.

I would check so see if there is actually any output from the socket as a first step - is the socket full of crud / corroded?

[AndyThomson]

Its a little dirty but nothing horrendous. With the engine running I've not been able to get any output registering on the multimeter, but there's no guarantee I'm using it correctly.

[GiveMeABreak]

So you'll need to investigate further then and see how it's all been put together ( )

[AndyThomson]

Took a fumble the wiring last night & found a connector with a fuse taped to the outside of the block. Stuck it in & all appears to be well!

...except now I'm left curious about why that would have been done in the first place; Could it just be to stop the horrendous beeping that now comes with the indicators (that transported me jarringly back to my childhood in the 90's)?

[GiveMeABreak]

... or worse. sounds dodgy to me and makes me wonder why it was disconnected - I'd be very cautious. If it were me I'd be raking it out and putting a proper harness in place.

[AndyThomson]

Something of a bird's nest in there, but would at a glance to appear to be splicing into the harness for the rear light cluster logically enough.

Abysmal placing of the (relay?) box for ready access, but I don't imagine you should have to do that too often.

[daviemck2006]

I would be tempted to get that looked at by someone who knows what he is doing, such as an auto electrician or the like. It does not look like its factory fitted.

[Paul-R]

...except now I'm left curious about why that would have been done in the first place; Could it just be to stop the horrendous beeping that now comes with the indicators (that transported me jarringly back to my childhood in the 90's)?

Do you mean the volume/tone of the beeping that matches the flashing of the indicators? This may be by design.

[AndyThomson]

It really doesn't look OEM, does it?? I feel the single fat zip tie syncing most wires into a bundle is the dead giveaway!

The tone is definitely intentional, as you say its the one that times with the indicators, that's quite harsh on the ears & I don't think I've heard since the Nissan Bluebird my dad used to drive got written off when I was about 11!

[Paul-R]

Anything with Scotchlock connectors won't be OEM!

[PaulC5]

When our C5 is not used for towing I pull the towbar fuses out. The car is not used much and the towbar electrics put a slight drain on the battery. The relays are hidden behind panels so the indicator beeping is not too loud so on the 207 you could try a bit of insulation to muffle the sound. The fuses need to be in for the MOT.