In article ,
Steve wrote:
hi, Fiat Punto 1.2 petrol w reg year 2000 has apparent varying light
brightness to headlights and interior lights. when stationary and rev
engine lights tend to brighten then dim. this applies also to interior
lights. When driving along the road in darkness, the lights tend to
vary in brightness. any ideas ?

Get a DVM and measure the voltage at the battery (lights on) at idle and
with the engine running faster so the lights are at their brightest and
report back. Some variation in brightness could be normal on that model.
But that could be proved by knowing the voltages are within tolerance.

You could also try charging the battery with an external charger and see
if the difference between bright and dim is still the same.

When actually moving, I'd not expect to see any variation in the lights.
Alternators tend to reach their peak output at quite low revs.

--
*Beware - animal lover - brakes for pussy*

Dave Plowman London SW
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