Technical Front fogs
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Technical Front fogs
A 2008 Ducato will probably have a bulb failure warning system. You won't be able to break into any of the existing lights wiring.
I wouldn't be breaking any wires just piggybacking on them so that when I switched on the parking lights it would also operate a relay which would light the fogs.Just don't know where it would be best to do this.
OK I think I know what you mean.is that the warning system would see my fogs as blown when I wasn't using them,is that right.
OK I think I know what you mean.is that the warning system would see my fogs as blown when I wasn't using them,is that right.
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No... the bulb failure warning system works by comparing the resistances of each bulb and it's associated circuit with a known standard value. Any interference with, or modification to, the circuit will trigger a bulb failure warning.
Hi, the late Fiats have a very intelligent bulb failure warning system, but with a bit of homework you may still be able to pick up a park light feed. Firstly, try a protected relay off the front park light, the winding shouldn't be enough to cause a problem, most bulbs aren't made to an exact tolerance, and a mini relay should only be about 140mA. It won't hurt the system, but if you overload it with something that small, bringing up the failure light, simply disconnect the relay- turn lights off, back on, and the module is reset.
Secondly, check to see if glovebox light, lighter illumination light, etc. are fed off park lights. These are not usually on a bulb failure circuit, but don't use main panel illum circuit, as these are often on a dimmer.
Thirdly, use a solid state relay. I use one to operate reverse cameras on Mercs, they can be connected directly to your chosen circuit, and to earth, the voltage switches the SS relay, but with a digital multimeter, you won't see any current draw. This is the most expensive option, but suits my purpose for the Mercs, their lights are all monitored also.
Options aren't listed in best to worse order, try any of them.
As an interesting aside, a customer had a 2009 Fiat, and it had been fitted with hi level LED stop/tail/flasher lamps. The driver got stopped by a passing motorist to say you have no tail lights, when she got to her destination, she checked and they were working. This happened on 3 separate occasions. After checking the lights, I found that the LED lamps weren't overloading the tail cct, til the stop lights were activated. Tails would go out and stay out til light switch turned off and on. Next time stop lights activated tail would go out. It turned out the dual brightness stop/tail lamps weren't well protected internally, and stop cct backfed into tail, , which changed the current draw being monitored by the BCM. I fitted a diode on each side tail input, this fixed the problem. These LED tail lights drew 50mA each, so 100mA doesn't overload the system.
Secondly, check to see if glovebox light, lighter illumination light, etc. are fed off park lights. These are not usually on a bulb failure circuit, but don't use main panel illum circuit, as these are often on a dimmer.
Thirdly, use a solid state relay. I use one to operate reverse cameras on Mercs, they can be connected directly to your chosen circuit, and to earth, the voltage switches the SS relay, but with a digital multimeter, you won't see any current draw. This is the most expensive option, but suits my purpose for the Mercs, their lights are all monitored also.
Options aren't listed in best to worse order, try any of them.
As an interesting aside, a customer had a 2009 Fiat, and it had been fitted with hi level LED stop/tail/flasher lamps. The driver got stopped by a passing motorist to say you have no tail lights, when she got to her destination, she checked and they were working. This happened on 3 separate occasions. After checking the lights, I found that the LED lamps weren't overloading the tail cct, til the stop lights were activated. Tails would go out and stay out til light switch turned off and on. Next time stop lights activated tail would go out. It turned out the dual brightness stop/tail lamps weren't well protected internally, and stop cct backfed into tail, , which changed the current draw being monitored by the BCM. I fitted a diode on each side tail input, this fixed the problem. These LED tail lights drew 50mA each, so 100mA doesn't overload the system.
High level brake light is probably LEDs and not connected to the bulb failure warning system.