Alternator Trouble ? Advice please

derv

I'm having a bit of trouble with the alternator / battery in my car.
Well at least that's what I think it is so looking for some advice or suggestions etc...


The car was struggling to charge for ages, and would go dead after leaving the radio on for only a few mins. So i put in a new battery which seemed to fix the problem.

But the other day the car would not start, not even turning over. Completely dead.

So i jump started it and it was running for about 10 minutes, went out to drive it, turned on the lights and the car died completely.
Tried this a few times , same thing happened.

Even after driving for 20 mins, then turning off the engine, and trying to start it again - nothing at all.......

When the engine is running, the belt is turning fine and seems pretty tight.

Any ideas on what else it could be or what else to try?

Thanks

crosstownk

You'll need to have the alternator checked to see if it is charging the battery. You can do a quick check with a voltmeter, if you have one. With the engine running the voltage at the battery terminals should be around 14volts and around 12v with the engine off.

Even if you can't do it yourself, have it done soon in case it damages your new battery.

How long ago did you replace the battery?

tom1979

any easy way to see if its charging

start your car

then turn on you full head lights

the engine idle should fall if the battery is charging ie the revs drop
hope this helps

derv

cheers lads.

the battery was replaced about 2 - 3 weeks ago but the car was not driven far at all since. not even 100 miles


if i leave the car running idle and turn on the headlights , the car will die completely.

peasant

Your alternator isn't charging ...have it looked at by a car electrics specialist, maybe it can be repaired cheaply rather than buying a new one.

DublinDilbert

derv wrote: »

cheers lads.

the battery was replaced about 2 - 3 weeks ago but the car was not driven far at all since. not even 100 miles


if i leave the car running idle and turn on the headlights , the car will die completely.

It does sound like the alternator, but you'll need to get someone with some electrical experience to test...

If you have a multi meter or can get one (maplin do a cheap one for €10), myself or the guys here will tell you how to do some simple tests.

My guess would be that one of the diodes in the alternator rectifier has possibly failed.. this will have 2 consequences, the battery will not charge correctly when the engine is running, and when turned off the alternator may well start to drain the battery. If you can pop out the alternator you should be able to test the diodes fairly easily with a meter. There's also a set of carbon brushes in the alternator they chould simply be worn out, can usually be replaced very cheaply.

Price a re-conditioned alternator, of if your near a scrap yard you might get one for 1/2 nothing...

tom1979

you could pic up 1 at a scrap yard for little or nothing
it will be tested with warranty save a fortune rather than buying a new 1

snowman707

Is the the red battery indicator light coming on in the dash. when you turn on the ignition??

In some cases this bulb also acts as a fuse & if not working then your alternator will not charge the battery


If it is working & staying on when the engine is running then most likely your alternator is faulty, best get the alternator checked next, most likely a cheap repair

PS check the light in the dark, even if it is glowing ever so slightly ,

check the connectors on the alternator it self

Fishtits

Make, Model & Year?

derv

its a 1998 honda civic coupe 1.6 ils


nope the light is not coming on in the dash snowman.

Rovi

derv wrote: »

its a 1998 honda civic coupe 1.6 ils


nope the light is not coming on in the dash snowman.

Not coming on at all, or coming on when you switch on the ignition and going out when you start the engine?

jayok

derv wrote: »

its a 1998 honda civic coupe 1.6 ils

Ah - I had an issue with a 1998 3dr 1.5iLS and these quite some time ago. There was a problem with voltage regulator in one of the makes used (bosch or mitsui or something like that) in that it would not output the correct voltage sometimes too high, sometimes too low. I am trying to remember the TSB (it was seven years ago) but it was sometime like the regulator will continue to fail and may result in a dead battery. Honda's Solution: Replace the alternator.

So I got the alternator replaced and it worked perfectly for the next three months. But alas, I put that car into a ditch and wrote it off so the alternator may have failed again!

derv

rovi i'll check that again shortly.


jayek cheers for that . any idea how much it costs to buy a new one from a motor factors ?

DublinDilbert

derv wrote: »

rovi i'll check that again shortly.


jayek cheers for that . any idea how much it costs to buy a new one from a motor factors ?

I wouldn't go near a motor factors for one...

Just get a reconditioned one, the likes of myles balff there in phisbro if your around dublin. I'd guess you'd be looking at €40-€50 euro for a reconditioned one....

derv

there is no light coming on in the dash whatsoever.

i drove from galway to dublin today. and when i got there, turned off the car, tried to turn it on straight away - and nothing...... completely dead.

i tested the new battery with a meter and it read completely dead.... ?

i have been having problems with the central locking - could that be draining the battery ?

it was also suggested by a guy that i may have got a dodgy battery and should get it replaced where i bought it

snowman707

derv wrote: »

there is no light coming on in the dash whatsoever.

i drove from galway to dublin today. and when i got there, turned off the car, tried to turn it on straight away - and nothing...... completely dead.

i tested the new battery with a meter and it read completely dead.... ?

i have been having problems with the central locking - could that be draining the battery ?

it was also suggested by a guy that i may have got a dodgy battery and should get it replaced where i bought it

Before you do anything else get your alternator checked##


Do not run away & buy 1 , you need to find out if your own 1 is faulty or not, when you have the alternator either fixed or dismissed as not your problem, you can start looking at other possible items

Avns1s

If the alternator light is not coming on at all, it generally means that the brushes are worn, unless you've been very unlucky and the bulb has blown at the same time as the alternator has become faulty.

Get a refurbed alternator or get the brushes done in a place that does the refurbs, probably be the same price. Oh and get that new battery charged up as quickly as possible or you'll need another one of them too. They don't like being discharged fully, particularly for long periods!

snowman707

Avns1s wrote: »

If the alternator light is not coming on at all, it generally means that the brushes are worn, unless you've been very unlucky and the bulb has blown at the same time as the alternator has become faulty.

Get a refurbed alternator or get the brushes done in a place that does the refurbs, probably be the same price. Oh and get that new battery charged up as quickly as possible or you'll need another one of them too. They don't like being discharged fully, particularly for long periods!

If the bulb is blown the alternator may be working ok

he has already bought a battery which most likely was not needed
why buy an alternator when all he needs is bulb costing less than €1 ??

Avns1s

snowman707 wrote: »

If the bulb is blown the alternator may be working ok

he has already bought a battery which most likely was not needed
why buy an alternator when all he needs is bulb costing less than €1 ??

If it was only the bulb was blown, the battery would still be getting charged by the alternator.

I think you might want to re-read my post.

DublinDilbert

Avns1s wrote: »

If it was only the bulb was blown, the battery would still be getting charged by the alternator.

I think you might want to re-read my post.

Ummmm i think it was mentioned above, that depending on the type of alternator and the way its wired on the vehicle, "some-times" the bulb provides the small current needed by the voltage regulator.

However on most alternators this is not the case.

Fishtits

"Ummmm i think it was mentioned above, that depending on the type of alternator and the way its wired on the vehicle, "some-times" the bulb provides the small current needed by the voltage regulator."

Correct.

At the rear of your alternator there is a loom plugged into it, remove this plug and look into it. There will be four connectors, turn the plug so that the you have two horizontal connectors side by side and at the top. You should have two vertical connectors at the bottom. The vertical connector at the bottom left is the charge lamp connector - earth this connector and the charge lamp should come on. If it does - the alternator is faulty, if it doesn't - the problem is most likely a blown bulb.

The other bottom connector should have a live feed when the ignition is switched on. Don't put anything near the top connectors - one is connected to the ECU.

snowman707

Avns1s wrote: »

If it was only the bulb was blown, the battery would still be getting charged by the alternator.

I think you might want to re-read my post.

Not Always

& I learned this the hard way but i admit i am not familar with th OPs vehicle perhaps you have better knowledge

I recall a student who worked for me many years ago had a charging problem with a car he bought

It was eventally found that the previous owner that fitted a wrong bulb which wasn't the correct rating, we lost a full day on that car.