Alternator/Battery light

[kojak]

My battery light keeps flickering when on tick over (950/1000) once the engine is warmed up. If I gently touch the gas pedal, it goes out. It seems ok when its cold. Is this the alternator on its way out, or is there anything else that could cause it....diode pack whatever that is. The battery was new 18 months ago, and is 'fully charged' up according to the accumate. (just been out for a run, connected the accumate up, and it shows charged)
Also, at the back of the alternator, there is a spade terminal with nothing to it! Is that anything?

[cirvy]

Mine did similar a couple of years ago, unfortunately it was the alternator with mine!

[kojak]

I did a search and someone mentioned a diode pack. Could this be the problem not knowing what it is. Also, how long a job is it to change the alternator on a 4.2, and how much?....and whats the spade connector thats got nothing on it.




off to work..be back later.

cheers.

[pjenni12]

I had the same problem with mine, turned out to be I had put the oil and charge light back in the wrong way round after a dash swap. Oil level was getting low and when warm would illuminate the light!

[RUSSELLM]

This probably doesn't help, but on a cold day, my battery light shows for the first couple of minutes.
My Alternator & diodes have been tested & have been found to be OK. Power mentioned some kind of sensor behind the dash, that may be over sensitive, but it's not worth me pulling the car apart looking for it.

Strangely, the Cerb's alternator doesn't charge the battery at tick over, you get less than 13.2 volts, in fact you get less than 12.2 volts On any other car you'd expect to see the battery light at that point

As an aside, A battery charger will show a battery is full, when it's full
However a healthy 70AH battery, will show full at 70AH.
An old 70AH battery with half it's cells knackered will show full at 35AH.

You need a proper battery discharge tester to get accurate ish readings.

[touching cloth]

Goes without saying to check your big fuse and also the quality of the connections to and from it - even if the fuse is ok (and it's probably worth changing it anyway just to eliminate it) if the connections are corroded for instance then it won't be able to transfer a nice strong charge.

[arebrec]

I'd also make sure you have a spare 100amp fuse when you go out and know how to change it.

I had the battery light flicking on and off and on and then finally car stopped on me, and was the 100amp fuse.

[arebrec]

hey TC great minds and all that

[kojak]

Never thought of the big fuse. As its a 2 minute job, i'll try that first.

Done this before, but cant remember whether I disconected the positive battery lead first and then just replace...or is it a case of being careful not to touch anything with the long socket?

Edited by kojak on Thursday 24th April 16:02

[Ballsy]

Wrap some electircal tape round the socket first so it doesnt short