There are some controllers that have more functionality.
When you connect a trailer to the tow wire harness on my '99 Suburban it
controls the trailer lights with no change in flash rate. So there are
controllers that will drive more than 2 blinkers at one time, the
original application may very though.
Paul Hunt wrote:
> Well, as far as I'm aware they all 'clink, clink'. But the modern
> electronic OE units wouldn't be any good either. Both old and new
> types are designed to work with two and two only bulbs (or equivalent
> loads), and both are designed to give an audible and visual warning of
> bulb failure. The older units stop flashing and leave the remaining
> bulb working as we know, the modern units flash at double speed. With
> the load of just a pair of LEDs they would be flickering away like
> billy-oh. The only flasher units that *might* work with a low load
> like LEDs are those after-market units which don't have a failure
> warning mode, and which are a serious safety hazard as a consequence.
> I certainly wouldn't want to be sitting in a lane waiting to turn
> across traffic with the flasher unit going 'clink clink' and the
> tell-tale flashing away as it should, not knowing that nothing was
> flashing at the back (or front). Without an equivalent load you would
> need a third way (designed by Blair, perhaps?) of flashing a pair of
> very low current LEDs whilst still giving an indication of bulb failure.