A Bizarre problem with bleeper reversing lights

Scattycat

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I've recently bought some replacement reversing bulbs that when engaged give out a bleep as well as lighting up.
They work fine on our little Clio but on the camper the light works but no sound.
I've checked the voltage at the light clusters on both vehicles and they are identical.
Any suggestions as to the reason?
 
How new is your camper?
Modern CAN Bus systems hate voltage fluctuations and can be very fickle.
 
Could well be canbus.

Anything other than the expected resistance in a particular circuit will cause the canbus to shut down until the extra load is removed.

Nothing you can do about it.

Even LED bulbs won't work unless they are canbus compatible
 
Canbus? Never neard of it. so, what exactly is it?

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Canbus? Never neard of it. so, what exactly is it?
CANBUS is in effect an electrical system controlled by a dedicated controller/computer. amongst other things, it measures the current drawn by each light circuit so can tell when a bulb fails or is the wrong type
far more complicated than that though but its only a broad description to explain your issue
 
It's a clever, single wire system to control lighting primarily.

Just one 12v wire feeds a control centre which receives low power signals to each lights control switch.
The signal triggers individual electronic relays and diverts power from the single 12v power wire to each light on that circuit.

It saves having a heavy wire going from switch to light in every circuit thus saving resources.
One heavy feed wire and a dozen lightweight trigger wires instead of a dozen heavy wires.

The downside is the trigger wires are load sensitive and only work at the correct resistance....your buzzers are altering that resistance.
 
Even wire length is pretty critical..... Lengthen the wire and it may not work.
CAN Bus uses a system of "nodes" to control circuits..... To be honest it's a pain in the arse to diagnose sometimes.
New generation CAN Bus is even more complicated, thank goodness I'm retiring and selling up this year !
 
Think my old Transit connect (2010) used something similar to this.
I fitted a tow bar but the lighting board would not indicate correctly:(
Ford dealer said he would re map the ecu for 70 quid due to the extra bulb :rolleyes:
I just removed the side repeater :LOL: it worked fine then(y)
 
Fitting towbar lighting requires a canbus bypass relay block.
Either dedicated or universal.

Dedicated is expensive but plug n play.
Universal needs splicing into existing wiring for the triggers but is much cheaper.

The relays work in the same way....one main 12v feed and trigger wires from each lighting circuit plus a heavy wire from relay to lights.
As each light is switched it activates the corresponding relay and diverts 12v to that light or lights.

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Think my old Transit connect (2010) used something similar to this.
I fitted a tow bar but the lighting board would not indicate correctly:(
Ford dealer said he would re map the ecu for 70 quid due to the extra bulb :rolleyes:
I just removed the side repeater :LOL: it worked fine then(y)
It might be worth putting two LED bulbs in tot system as they would be about the same current
 
I've recently bought some replacement reversing bulbs that when engaged give out a bleep as well as lighting up.
They work fine on our little Clio but on the camper the light works but no sound.
I've checked the voltage at the light clusters on both vehicles and they are identical.
Any suggestions as to the reason?
If the light works, CANBUS or no CANBUS, then the light is receiving 12v. Although I have a reasonable grasp of CANBUS I'm not sure of the detail in terms of switching. The only way the light will work but the buzzer won't is if the 12v supply is reversed. Set the vehicle with the reversing lights on then use a meter to check that the centre pin of the bulbholder is at +12v rather than at earth. If it IS at earth then the buzzer won't work and there's no simple way to make it do so.
 
If the light works, CANBUS or no CANBUS, then the light is receiving 12v. Although I have a reasonable grasp of CANBUS I'm not sure of the detail in terms of switching. The only way the light will work but the buzzer won't is if the 12v supply is reversed. Set the vehicle with the reversing lights on then use a meter to check that the centre pin of the bulbholder is at +12v rather than at earth. If it IS at earth then the buzzer won't work and there's no simple way to make it do so.
Following on from the above comment ref positive/negative wiring.
I've just checked via a spare 12v battery and if the the centre of the bulb is connected to the positive pole the buzzer works but if connected to the negative pole then although the light works the buzzer doesn't.
So if I managed to re-wire the reversing light bulb holders so that the centre is positive and the outer negative would the canbus thingy see it as a fault, or, would this just give more problems that I haven't considered yet?
 
Following on from the above comment ref positive/negative wiring.
I've just checked via a spare 12v battery and if the the centre of the bulb is connected to the positive pole the buzzer works but if connected to the negative pole then although the light works the buzzer doesn't.
So if I managed to re-wire the reversing light bulb holders so that the centre is positive and the outer negative would the canbus thingy see it as a fault, or, would this just give more problems that I haven't considered yet?
The canbus would pobably see it as an overload.
the filament alone will have a known resistance....add to that the buzzer and the load is increased.
thats the reason for needing bypass relays for trailer wiring...it physically bypasses the canbus system and the canbus loads remain constant from the standard lighting.

Get it wrong and blow the canbus will be VERY expensive....usually part of the ECU.
 
The canbus would pobably see it as an overload.
the filament alone will have a known resistance....add to that the buzzer and the load is increased.
thats the reason for needing bypass relays for trailer wiring...it physically bypasses the canbus system and the canbus loads remain constant from the standard lighting.

Get it wrong and blow the canbus will be VERY expensive....usually part of the ECU.

Thanks, sounds like I'm stuffed then. LOL

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Following on from the above comment ref positive/negative wiring.
I've just checked via a spare 12v battery and if the the centre of the bulb is connected to the positive pole the buzzer works but if connected to the negative pole then although the light works the buzzer doesn't.
So if I managed to re-wire the reversing light bulb holders so that the centre is positive and the outer negative would the canbus thingy see it as a fault, or, would this just give more problems that I haven't considered yet?

why not try it with some fly leads, go careful so as not to blow anything but try having the bulb separate to the holder and wire in reverse, see if it works... might save the hassle of changing it all round only for it to not work
 
Wire directly to the reverse switch output wire on the gearbox and earth......only one wire to install back to front.

Loud at 95db

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From a legality POV I thought beepers were restricted to commercial vehicles.
 
I have found some reference to an offence called 'reversing alarm on unauthorised vehicle' but can't track down the source

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I have found some reference to an offence called 'reversing alarm on unauthorised vehicle' but can't track down the source

I can fully understand a ban on cars, there would be so many beeping they would become of no value.

A MH, with it's limited viz has a case but whether technically legal is another matter.
 
Thanks, sounds like I'm stuffed then. LOL
You will be OK - the buzzer draws so little current (a few thousandths of an amp) that the vehicle won't notice it at all given that the bulb will be taking around 2 amps when lit and more than double that when first turned on.
 
found it...

http://www.legislation.gov.uk/uksi/1986/1078/regulation/99/made

(3) No person shall sound, or cause or permit to be sounded, on a road any reversing alarm fitted to a vehicle—

(a)unless the vehicle is a goods vehicle which has a maximum gross weight not less than 2000 kg, a bus, engineering plant, or a works truck; or

(b)if the sound of the alarm is likely to be confused with a sound emitted in the operation of a pedestrian crossing established, or having effect as if established, under Part III of the 1984 Act.

damn... pappajohn beat me to it..

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You will be OK - the buzzer draws so little current (a few thousandths of an amp) that the vehicle won't notice it at all given that the bulb will be taking around 2 amps when lit and more than double that when first turned on.
all well and good however the canbus system on the fiat/peugeout vans is very sensitive. even fitting a cheap bulb can cause it problems like shutting off the circuit to protect the wires
 
all well and good however the canbus system on the fiat/peugeout vans is very sensitive. even fitting a cheap bulb can cause it problems like shutting off the circuit to protect the wires
It may be sensitive but bulbs (of any quality) are not close-tolerance devices. The current draw of different 21W bulbs varies by a couple of hundred milliamps from one to another - considerably more than the extra drawn by a buzzer. If the vehicle in question uses a 21W reversing light bulb it has already had to cope with the drop to the 20W halogen of the bleeper bulb. What I'm saying is that trying the bleeper bulb will do no harm - it might, as you suggest, cause the circuit to protect itself but that's easily cured by removing it.
 
Irrespective of being legal or not, if you arrive late at a site you won't be very popular reversing onto a pitch.. even during the day they make a hideous noise.

Had one on my RV and ripped it off for that very reason..
 
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Irrespective of being legal or not, if you arrive late at a site you won't be very popular reversing onto a pitch.. even during the day they make a hideous noise.

Had one on my RV and ripped it off for that very reason..
Yes, they are called bleepers for a reason...
 
Our Revising lights and bleeper went off tried everything to get it to work. Found on the Peugot there is a switch on the gearbox that completes the circut renewed said switch and all is now ok.Bit of a job had to remove air filter etc. to get into it.
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