BSI and Non PSA CanBus Parking Sensors

[Sloppysod]

Hi All,
I have owned Citroens for many years and have done mostly all of my own repairs apart from diagnostics, but that is about to change I have bought a Lexia rev C from E**y.
I have some questions, about the BSI unit, I know it is the main computer for the car but how does it know stuff? I am looking to put front parking sensors on the car, I looked at the genuine Citroen set £200 !! for what looks basically like the kits you can buy for £20-£30 from E**y. Now the Citroen kit (made by Meta) connects to the reversing light circuit, so it knows when reverse is selected and it also has a wire going to the BSI, I think this is the ignition control. Now the cheaper kits have the same set up but will they work the same?

The Meta kit works when the ignition is turn on for 20 seconds and about the same after reverse has been selected, so what I want to do is fit the wire that goes to the Reversing light to the brake light switch(so it works only when the brake light switch is active) and the ignition wire to the BSI, will the BSI work with a non Citroen approved item or would I be best if I connect the ignition live wire to the another ignition controlled terminal - cigarette lighter for example? I also plan to add a sensible sized capacitor to the brake light feed so it stays active for about 10 seconds after the brake lights have gone off.

Does anyone know the brake light feed from the BSI?

Here are the tow diagrams from the Citroen Fitting guide
- I don't know what has gone wrong, but you can copy and paste this into your browser.
Stu
Fixed it for you - you just need to put the code for the vid between the brackets RW

[wheeler]

Save yourself the hassle & get a normal aftermarket set that require just an earth & a reverse light feed. If you prefer you could just fit a switched live instead so you can switch it on & off manually. I wouldnt dream of paying £200 for the citroen one when you can get practically the sam thing off ebay for under £15. You can even get them already coulour coded.

[qprdude]

Am I missing something here? I read that you were fitting FRONT sensors. Not sure I understand the reference to reverse gear for front sensors. Probably be good to know what car you have too.

[hamster99]

Qprdude is right, tell us what car you have, including model, year, trim level and last 8 digits of VIN and members here will be able to provide more relevant advice.

In general, if you have a relatively modern Citroen (up to say 10yr old) then it may well have the wiring for parking sensors and all you need is the sensors and a bit of programming with the lexia.

[Sloppysod]

Sorry Guys for keeping it a bit vague,
My car, C5, 2.0Hdi Exclusive, auto, Mk3 2011Vin VF.....BL503207. (TRIM LEVEL - UPPER LOW PLUS - Basic Exclusive)
the Story.... My last car was a C4 B7, EGS, Exclusive, lovely car apart from the ride was not as good as the other 10 Citroens I have owned and I was not over confident that the gearbox was 100%, used to slip when changing gears from 4th to 5th & 5th to 6th when warm........possibly the DMF on its way out, at 46,000 miles!! and if you got into the car too quick, started it, put it into gear it would not move, you had to stop, turn it off, let the computer shut down completely (5 mins) then start again, was back and forth to main dealer for investigation under warranty but was never fixed. Anyway, the thing I miss from the C4 is the front parking sensors.
So, after an thorougher investigation, Citroen Service site, and emails back and forth to the manufacturer of the Citroen after market item (Meta - http://www.metasystem.it/index.php/msy_ ... ne/Citroen), which is basically an expensive Ebay kit, I am toying with the idea of adapting an Ebay can-bus kit (these kits have a separate live) to work on the front using the brake pedal as the trigger, instead of the reversing circuit. so going back to my 1st (ever) post, how does the BSI know what is connected, the OEM Accessory kit instructions say use the diagnostic equipment, and I want to connect my front installtion to the brakelight circuit and possibly the same live wire as the instructions, as I think that may be a speed sensitive trigger.
I have read on the Citroen Service that there are two types of reversing sensor controllers fitted to the C5, one is back and the other is both, it need to look and find which part is fitted to my car. 6590 CV, 6590 CW as the diagram does not show a rear unit.

thanks for your interest so far.
Stu

[vborovic]

I'd say you only have the parking computer for the rear sensors CV & CW being basically the same unit (internal different code, depending on the trim or something) ... with that, forget that you'll get any front sensors to work (aftermarket ones or even genuine), because you won't be able to connect them to anywhere (to work as a genuine solution) ... as for your other question about the BSI's knowledge of what is connected, that's why the car has about 20-30 computers, one of which is the parking sensor computer ... these computers communicate with the equipment, and communicate with the BSI ... if you would obtain the parking computer with F+R inputs (only for the Saloon, the Estate ones won't be compatible with your car), and connect the genuine front sensors, you'd still need to reconfigure the programming of the car, at least in 3 places: BSI, parking computer and the radio/nav unit ... like it was said before, definitely the cheapest solution would be to get any front aftermarket kit, and that's that ... if you would want to get the factory solution, you'd need to require the car a bit (I'd say the front wiring loom doesn't exists, that goes all the way to the back of the car) ... you should be able to check the exact parking computer which you have, it is behind the rear right wheel cover, inside the boot ... also, the CAN BUS is not that simple, because you have quite different data channels (different voltages), so aftermarket solutions may and may not work as expected due to this ...

I don't know how you planned to activate the front parking sensors with the break as the trigger, since that is far from the genuine solution ... the front parking sensors are active the entire time when you're driving below 10 kmh (~ 6 mph), the rear only when you're in reverse (fronts also work in reverse, if you have them).

[Homer]

The "CAN BUS / BSI" kit I got off ebay does not connect to the BSI, it simply has an extra +ive wire so it doesn't take too much current from the lighting circuit. The BSI doesn't know about it at all.

I'll have to have a look at the instructions again but IIRC it can be fitted as a front kit which is basically always active and just beeps when you get close to an obstacle.

Personally I'd stick to the old method of just turning the headlights on.

[Sloppysod]

vborovic - From what you say I am wasting my time looking for the part number of the controller as my car does not have the front to back wiring needed for front sensors, shame, would have been nice to have the center console display with a front & back visual.

Homer, Thanks for the information I think you understand exactly what I am thinking of, the only reason I am thinking of connecting to the BSI is that the "Genuine" Citroen aftermarket rear sensor kit connect to the BSI for its main power supply (+APC -conn GR16V, pos 6) and I have a feeling that the feed mentioned in the instruction may be speed sensitive, i.e. above 6 MPH no feed, therefore they are off.

So can anyone tell me what if "+APC -conn GR16V, pos 6" is just a 'ignition live or is actually a speed sensitive circuit?

thanks in advance
Stu

[vborovic]

You could check whether the front wiring exists, either by going under the bumper (maybe even removing it), or removing the rear boot trim/cover, so you can see which wires are there ... if you want the front sensors to appear on your radio/nav device as your rear ones do, I could (with 99% certainty) say no aftermarket solution will help you ... only genuine Citroen parts + the F+R parking computer + necessary wiring ...

If I understood the low quality photo from the YT video, that pos. 6, on the PH2 (official marking) connector, should be live (+) after ignition, for the electrochromed mirror

[Sloppysod]

Thank you all, I will probably let you know how I get on.
Stu

[Homer]

I had a look at the instructions for the set I have (not got round to fitting yet) and for the version with front and rear sensors the front ones are triggered off the brake lights and are active for 20 seconds after pressing the brakes.

Hope that's some help.

While we are on the subject, is there a live feed in the boot of a C5 X7 Saloon?

[vborovic]

I don't think so, since the Saloon doesn't have the 12V cigarette plug socket available, like the Tourer has ... but, it shouldn't be a problem to pull one through, if from nowhere else, than the rear seat cigarette plug ... although there are other options, even going all the way to the front (BSI area and the fuses)

[Sloppysod]

Homer thanks, I will look out for some with the delay feature, I can not see any problems with using the brake to trigger as my car is an auto and holding it on the brake while moving slow is natural.

Towbar - my next project, looking at the fitting instruction provided by witter www.witter-towbars.co.uk/uMedia/FittingElectricsDed/ZEKC0005.pdf page 7 picture 24, all they add is a 30 amp fuse to the fuse box (and register the towbar electrics on lexia), they do not run a new wire front to back, so there must be 12 volt live, it just is not yet.

[Sloppysod]

Hi, - Back to the Front parking sensors, I decided to fit some after market front parking sensors to my C5, with a similar display to Mercs (a small light bar at the base of the windscreen). My plan is to connect to the brake light switch, via a relay (this will keep my electrics away from the Car Canbus system) then a a 30 sec delay module, and and am now stumped,

- Am I reading the wiring diagram correct, in that there is only 4 volt going to the brake light switch?

[xantia_v6]

The 4V on the diagram is just an ID code, not a voltage reference.