Flickering Headlights

[Semmysonic]

I've notice the headlights Flickering possibly the dash lights too(at least I think they are) not all the time and not that often. I think it's as the engine is slowing down.

It's not a massive issue at the moment, just wandering if it's a sign (maybe the alternator is on its way out)

Not battery as it did the same when the battery was new.

[bignev]

Hi pal,

Our 2002 3.3 used to do that, never bottomed why.

 

Until the gearbox ecu had a marital (stopped talking) to the rest of the car it was fine.

[Semmysonic]

Hi nev, it also loses memory functions at random times while the car is running, again not a massive issue. It pops up on the overhead display, can't remember exactly but something about memory can't be changed when not in park. Just another one of those strange things with these cars :-)

[andyb2000]

This sounds like a potentially faulty alternator/regulator not quite smoothing the voltage out, you'll probably start to find the battery looses charge faster which is normally associated with memory functions, dash needle sweep, etc.

 

Get the alternator checked sooner rather than later, if it's sending out spikes or ripples through the electrical system the battery will help smooth it out but not completely (It will also shorten the life of the battery), this could lead to ECU or damage to other components if left too long.

[Semmysonic]

What's the best way to test the alternator?

 

Memory thing happened with a brand new battery on. Plus it happens when the car is running and not at startup,its an odd one for sure.

[andyb2000]

Unfortunately this isn't easily done, using a standard digital multimeter isn't normally accurate enough, nor can you test the regulator pack, etc, effectively.

 

The basic check is with ignition off, multimeter on battery and see what voltage you get (12.5v ish) then startup and wait a minute, then check again (14v ish), it shouldn't spike or jump above 15v and definitely shouldn't dip low.

Put on headlights and see if voltage dips low, if it drops down below 13v I'd say cause for concern, or if you find the meter readings jumping a lot (Again depends on the meter, cheaper/basic ones aren't very good at giving you rapid changes in voltage).

 

BTW, no matter what info you find, DO NOT disconnect battery when engine is running, you've got the potential of frying ECU and others doing that!

[scrufgp]

i had similar problem with my old 2.5crd voyager 

light flickering dash flickering etc.......

took it auto electrician who diognosed voltage regulator !!!

that happened to be part of the ecu which meant a very costly repair for me in way of ecu replace or reprogramme

i ended up living with it flickering !!!!

hope this helps