NB (1998) Battery charge warning light solid on - Help

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Dommer
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Vehicle: NB8A

NB (1998) Battery charge warning light solid on - Help

Postby Dommer » Thu Jan 02, 2014 6:28 pm

Replaced timing belt and water pump during Christmas break, all went well. Until 2 days later ( after less than 10 Km), the charge warning light come up (after I restart the motor in a car park). Not sure it is related or pure coincidental.
Replaced alternator with new after market (from ebay) did not resolve the problem.
Battery and alternator terminal while off read 13.95 volt. And with engine running (head light off) reads 14.18 volt, with head light on reads 14.25 volt.
The P terminal (grey wire) reads 5.32 volt, and pulse voltage of about 3 volt AC are detected on the D terminal (grey/red wire); which seem to suggest the alternator is charging (from what I have Goggle), but the red charge warning light stays solidly on.
Appreciate any help or suggestion. Or if anyone can recommend me a auto electrician in Melbourne Eastern suburb.
Thanks all in advance.

Mr Morlock
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Re: NB (1998) Battery charge warning light solid on - Help

Postby Mr Morlock » Fri Jan 03, 2014 9:45 am

Auto elect - Boronia Auto Elec Service Phil 9729 7299 ( Macquarie Place or Ferntree Gully Auto Elec Joe - Amay Cres 9758 1316 . Late advice but always best to get a diagnosis first- the "old" alternator might be ok.

Dommer
Learner Driver
Posts: 9
Joined: Mon Mar 04, 2013 11:06 pm
Vehicle: NB8A

Re: NB (1998) Battery charge warning light solid on - Help

Postby Dommer » Fri Jan 03, 2014 1:32 pm

Mr Morlock, appreciate your response.
Already took it to McDonald auto electric in Ferntree Gully (recommended in some old thread here) this morning. The initial diagnostic from Russell still the alternator. He will look at if he can revive the old one. More work and update to be done on Monday, as he is closing this afternoon.

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KevGoat
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Re: NB (1998) Battery charge warning light solid on - Help

Postby KevGoat » Fri Jan 03, 2014 2:01 pm

Dommer ... I had a similar problem with my NB. This may or may not be the problem, but the original alternators are externally regulated by the ECU. If the replacement you bought from ebay is internally regulated, the warning light will continue to be displayed. To resolve this, I used the following wiring mod from Miata.Net:

Image

Dommer
Learner Driver
Posts: 9
Joined: Mon Mar 04, 2013 11:06 pm
Vehicle: NB8A

Re: NB (1998) Battery charge warning light solid on - Help

Postby Dommer » Sat Jan 04, 2014 7:22 am

KevGoat, Appreciate your response. The alternator I got supplied is
http://ishop2.cooldrive.com.au/products/65-6221 which is definitely for NB seem to suggested is PCM or ECU controlled. That was why I was completely lost. It is now with the auto electrician, who still believe it is the alternator, which will cost over $400.- just on parts. May try wrecker to source another Hitachi one on the week end. Many thanks again for your input.


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