Somethings not right - electrical

[Deutscher]

Hi All,

My car is having a little trouble atm.

It's a 96 VS S2 Calais. Battery is a 660cca (about 1 year old). Stock alternator. Running usual 4gauge cables around to alternator, battery, engine.

The battery is showing "not charging correctly" or something like that, not holding charge or something I dunno. It's not normal anyway. It's a Supercharge battery which shows Green for good, red for dead, white for charge issue or something.

Anyway, I was driving along the other day, got to the traffic lights and stopped. I have my stereo on (only currently running 4 channel x 70rms amp (4gauge) with some speakers) nothing major at all, (used to also run a mono 2600rms x 1ohm with a sub rated for 2400rms (0gauge), and it hadn't occured before).

When I got to the traffic lights, I wanted to do my windows up and I could see on the dash the light dim, also, when I've driven for awhile and stop at traffic lights my car sometimes looks like its about to stall ... the revs drop and the whole car shakes like wen your about to stall in a manual.

I was thinking a battery or alternator problem, I was running a lot of power before with my sound system with a stock alternator and think maybe my alternator is about to die and not charging properly.

Anyone know the source of the issue? is it the alternator or the battery? or something completely different?

[pillzor]

i would guess alternator but im no expert.

[hako]

Use a multimeter to measure battery voltage whilst the engine is running - should be over 13.6 Vdc at idle - if under 13 vdc it indicates you alternator is failing although if it's been happening for some time the battery would be near flat. If the alternator is not charging correctly and you are running a lot of electrical items - A/C, headlights and stereo for example, the alternator cannot generate sufficient power to keep the battery voltage at a level sufficient to keep the engine running (the ECU will not let the car run if volts are much below 12vdc).
Also I'd check battery cables - make sure they are clean and on tight.
Good Luck.

[Deutscher]

i would guess alternator but im no expert.

That's what I was thinking, Just didnt want to do the whole change one thing and not be it then have to replace other thing and may not be it either. Don't want to take it to a mechanic cause they'll charge what it costs to replace both of them anyway.

[tt460]

Id go with what hako is saying, i would also clean the terminals on the alternator and see how it goes, it might just be a dirty or bad connection.

[Deutscher]

Id go with what hako is saying, i would also clean the terminals on the alternator and see how it goes, it might just be a dirty or bad connection.

I know my battery terminal end is tight and clean. Just gotta check the alternator end... unfortunately its kinda raining a lot at the moment.

[Deutscher]

I've been told you can test your alternator by using a volt meter on the positive and negative terminal on the battery? is that correct? should be above 12V always, turn on all electricals and check again... if drops below 12V it means bad?

[scozz76]

Check the connection on your alternator, the B+ wire (big one). I've had a problem with this on my VS and a mates WH Stato. Undo the nut, clean the surface of the wire connector and alternator stud. If the wire looks burnt, wrap some electrical tape around it to stop it from earthing (shorting) out. If the wire and/or connector looks badly scorched, replace that entire run.

On mine, the battery light would come on when starting and slowly fade out. Then when you turn the lights on, the battery light would flash.

Also check the regulator/brushes (black box on the back of the alternator).

[Deutscher]

Well ....

I've checked my battery when cars off ... 12.4V ... started the car ... turned lights on, high beam, cranked stereo, ac on ... checked battery again ... 13.4 or 13.6. Could there still be some sort of alternator/battery problem?? or does that eliminate it?

The indicator on my battery shows Low Battery Charge. The car hadn't been driven too often (couple times a week for the past 3 weeks), maybe thats the reason for the low light ... ive always had a bit of a drain due to some electrical issue since the start.

When I stop at a traffic light, the car was normal temp and it felt like it was about to stall ... the revs dropped and then it jumped back to normal and kept doing that every few seconds.. when this happened I had my stereo quite loud (it's only currently running 4 speakers of a amp (65rms per channel). While this happened I pressed my window electrics button and they lights on my dash dimmed while I pressed the switch.

My dad said it a fuel issue for the almost stalling.. but im not sure about that.. because of all the symtoms i've explained... unless they all just happened at once and it doesn't happen for ageas... I have to be driving for like 30+mins before it starts happening (thats why I mentioned my car was normal running temp)

Another thing ... lately when I start my car it's rough idle ... just give it a lil rev and it's fine (was tinking maybe its just cause its a little colder these days in the morning, doesnt do it later). So when I start moving its fine.

I hope something out of all this ramble someone could find a fix?? or letting me know if it's an electrical or mechanical/fuel issue.

I think I've mentioned every bit of info I can think off. If anyone has questions.. feel free to ask.

[hako]

I still think it's basically that your alternator cannot keep the charge up to the battery - plus the battery, despite being 660CCA and only 1 year old, is not fully charged. Your reading of 12.4V is low - it should be 12.8V......the figures you quote (13.4 to 13.6V) are OK and indicate the alternator is good, so that gets beck to the battery.
So, my suggestion is to first charge the battery - if you don't have a battery charger borrow one from your old man or buy one - they are under $20 - charge the battery overnight so that by morning the battery will be fully charged. Make sure you disconnect the negative terminal from the battery when charging. Then in the morning reconnect the battery and see how it goes.....
Good Luck.

[tt460]

Also remove the caps and check the fluid level, you can top it up with water but not tap water you need demineralized water you can buy this in your local supermarket in the same isle as the laundry products. Also whilst it is charging have a look in each cell and make sure each cell is bubbling.