Re: Brilliant idea needed!!!

" Geocacher" <gps@xxxxxxxx> wrote in message
news:dgu6ht$g24$1@xxxxxxxxxxxxxxxxxxxxx
> I work in the trailer manufacturing business.
> We use LED tail-light clusters.
> The modern truck/tractors utilise a computer system to perform diagnostics
> on various systems within the rig. One of these is the lighting system.
> A pulse is sent to each tail light, the system monitoring the current. If
> there is current flow, it is assumed the incandescent globes are OK.
>
> Unfortunately, the LED lamps draw such a small amount of current that the
> computer does not see a "filament" and flags a major fault on the truck
> dashboard. In addition to the error message, the system continues to send
> curent pulss in the forlorn hope that things at the rear of the rig have
> improved. This causes the entire suite of LED lamps to flash like a
> low-class disco!

The first thing that comes to mind is to place a lage capacitor (1000uF?)
across the LEDS, to draw a high current pulse during the test, providing the
test is short enough. But I suspect this will flash the lights as well since
the cap is discharged through the LED's.

Meindert


.

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