ARC "bulb inefficient"

[David Masters <david@domain.elided>]

Fellows,

I have spent a large part of the weekend tracing wiring to sort out several 
flashing lights on my ARC display.  Although the car is an ALFA75 (Milano) 
twin spark, I believe it is largely the same as the more widely distributed 
V6 Milano.

Whilst I have had a little luck in finding that the "Brake fluid minimum" 
switch and the "disk brake pad wear" sensors use the same relay in the 
engine bay, I have not been able to work out how the "bulb inefficient" 
lights for either turn signals, or stop lights, work.  I have a warning 
light showing for these, yet all the bulbs work.  I have moved the bulbs 
around in the sockets, and there is no change.  All known earths and 
connectors have been cleaned and reassembled.

So, does the ARC actually use the resistance of the filament, and does this 
change over time?
All help appreciated.

Cheers,
david
ALFA75 TS, ARC "Christmas Tree"

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