Ignition light staying on

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ScimiTom
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Ignition light staying on

Post by ScimiTom » Tue Feb 19, 2019 12:27 pm

I know there are a couple of threads on here to do with the ignition light staying on, but has anyone experienced these symptoms:

The ignition light on my 5a is flickering at idle, then glowing brighter with increased revs, and staying on while driving. The voltmeter is reading as normal (around 13V, I think) and the car is driving as normal (for the short distance I travelled). I don't know how old the alternator is, but the plug and wiring were replaced six years ago.

I've read that an A127 is the alternator to go for, but is there anything else I should be trying before splashing out on a new part?

Thanks in advance.

Tom


Current: 'Boffin' (1971 SE5a)
Previous: 'Sunshine' (1980 SE6b)

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ScimiTom
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Ignition light staying on

Post by ScimiTom » Thu Feb 21, 2019 2:03 pm

I've tried turning the headlights on, then starting the engine. The headlights got brighter on start-up. So, should I conclude that the alternator is charging and doing its job, and that the fault is with the ignition light wiring? Again, on a short drive the car behaved impeccably. Any ideas are appreciated.


Current: 'Boffin' (1971 SE5a)
Previous: 'Sunshine' (1980 SE6b)

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Ignition light staying on

Post by philhoward » Thu Feb 21, 2019 2:55 pm

It'll be the regulator or rectifier circuit at fault - sometimes replaceable depending on the unit currently fitted (I'm assuming it's the 17ACR).

Found this with a quick google which is pretty good: http://www.lotus-europa.com/manuals/mis ... /17acr.pdf


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Ignition light staying on

Post by peter freeman » Thu Feb 21, 2019 8:22 pm

In the past I have had problems with he diode pack inside the alternator - dry joints and difficult to re-solder. Problems with the ignition light circuit seem to be affected most - don't forget this circuit is the regulator circuit so the alternator knows what voltage is being generated on the battery terminals - loss of this control can cause over voting which is not good for the battery or the other electrical items in the car - bulbs can be brighter and blow.



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Ignition light staying on

Post by ScimiTom » Sun Mar 17, 2019 9:08 pm

Just a quick update on this - I fitted a new 17ACR 50 amp alternator and the problem is now solved. I decided to go with the simpler (if more expensive) approach. Thanks for the suggestions.


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Ignition light staying on

Post by peter freeman » Sun Mar 17, 2019 9:10 pm

Sensible



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