Mazda 323 - Battery not working then works

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Sat 19 Jun 2010 01:31
Mazda 323 - Battery not working then works - Car

Went out for short trip this evening, stopped car and left lights on max 5 mins, went to start car and it would not start so called out breakdown services.

Tried car 30 mins latter and it restarted, would could of caused this?

Car is used for short journeys as second car covering around 1600 miles per annum, maybe this could be a factor.

Thanks.

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Sat 19 Jun 2010 02:09
Mazda 323 - Battery not working then works - 1litregolfeater

A flattened battery will regain some power if you let it rest for a bit, it's normal.

5 minutes sounds a bit quick to flatten it, maybe it's past its best.

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Sat 19 Jun 2010 09:53
Mazda 323 - Battery not working then works - Car

Thanks will get battery checked out.

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Sat 19 Jun 2010 13:13
Mazda 323 - Battery not working then works - Peter.N.

Check and clean the battery connections.

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Sun 27 Jun 2010 14:38
Mazda 323 - Battery not working then works - Car

Just got back from a short break, car battery was flat, so had to breakdown services out who got car started.

Car was then driven 10 miles and started up fine this morning when we took it two places for the battery to be tested, results as below

(1) First place reported batteryh had 47% capacity with altenator putting through 13.6 V after 3 mile journey from cold.

Then drove to second place i.e 23 miles away

(2) Second place reported battery had 51% capacity with alternator putting 13.4v.

So alternator ok, but need advise re battery capacity.

Thanks

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Sun 27 Jun 2010 15:45
Mazda 323 - Battery not working then works - Collos25

I find it absolutely incredible that they have not done a discharge test and told you that the battery is ok or had it.

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Sun 27 Jun 2010 16:15
Mazda 323 - Battery not working then works - Car

I find it absolutely incredible that they have not done a discharge test and told you that the battery is ok or had it.

The two tests both places did were, the first one was to connect the probs to the terminal with every thing switched off, which gave the capacity as 47 and 51%, the second car was started then rear heated window put on which showed the alternator putting a charge of 13.6% and 13.4%. So could one of them be a discharge test, also why would the capacity start going up, is this the effect of driving the car and subsequent driving will result in a battery at near full capacity? Thanks
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Sun 27 Jun 2010 16:19
Mazda 323 - Battery not working then works - Peter.N.

I would say that your alternator output is low, after half an hours driving 14.0 volts should about the figure. I would consider 13.4 volts insufficient to give a full charge within normal driving time. The fact that you had two different readings would suggest a faulty alternator regulator.

Edited by Peter.N. on 27/06/2010 at 16:23

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Sun 27 Jun 2010 17:12
Mazda 323 - Battery not working then works - Car

I would say that your alternator output is low, after half an hours driving 14.0 volts should about the figure. I would consider 13.4 volts insufficient to give a full charge within normal driving time. The fact that you had two different readings would suggest a faulty alternator regulator.

13.6 v was after 3 miles, 10 minutes driving and 13.4 v was after 23 miles and 30 mins driving which was done straight after the first test. How do you test for a fualty alternator regulator?

Thanks

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Sun 27 Jun 2010 19:04
Mazda 323 - Battery not working then works - Peter.N.

The alternator voltage should remain constant at around 14 volts, it will start lower due to the load of a partially discharged battery but certainly after a journey it should read 14v unless just started again. You may well find that the the voltage drops lower than that. If you connect an ordinary multimeter on a range that will read 12 - 15 volts to your cigar lighter you can watch it while you are driving, The only other possibility is a slipping alternator belt.

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Sun 27 Jun 2010 19:50
Mazda 323 - Battery not working then works - Peter D

13.4/13.6 is too low. 14.2 at 15 degrees from start up and 13.9/14 volts at 25 degrees. I suspect a faulty rectifier pack, you may have lost a diode to the charge waveform is not correct. Regards Peter

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Mon 28 Jun 2010 00:04
Mazda 323 - Battery not working then works - Car

you may have lost a diode to the charge waveform is not correct. Regards Peter

Please explain, thanks
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Mon 28 Jun 2010 00:03
Mazda 323 - Battery not working then works - Car

The alternator voltage should remain constant at around 14 volts, it will start lower due to the load of a partially discharged battery but certainly after a journey it should read 14v unless just started again.

Car was driven to test place switched off then turned onto test.

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Mon 28 Jun 2010 00:09
Mazda 323 - Battery not working then works - Peter.N.
Pretty sure to be the alternator or at least the regulator within it. You may be able to just change the regulator but its possible that the brushes are worn. I would try a breakers.

Edited by Peter.N. on 28/06/2010 at 00:10

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Mon 28 Jun 2010 00:29
Mazda 323 - Battery not working then works - Car
Strange that both places said alternator was working correctly ?
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Mon 28 Jun 2010 11:13
Mazda 323 - Battery not working then works - Peter.N.

It is, I've been working with alternators ever since they replaced dyanamo's and 14 volts is the norm, sometimes even a little over, much below that and the battery will not fully charge. I don't know how that relates to your original fault though.

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