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MG MGB Technical - Ignition red led

Hello, i have a 74' B GT.
A few days ago, I noticed the red "ignition" led was staying on even while I was driving.
I am not sure what the problem is and I have the impression the battery level is still ok and hence the battery is charging normally (I heard it could be an alternator problem).

If you have any clue on what the problem could be, let me know.
Thank-you very much in advance.

Thibaut
Thibaut

Hi Thibaut.

If your fan belt is OK, you almost certainly have an internal fault in the alternator.

Don
Don

Now would be a good time to replace the alternator with a Delco or a Bosch unit that puts out more power. Plenty of good articles on the web about this easy and well worthwhile fix. Alyn
Alyn

Check the system voltage on the brown at the fusebox with the engine running at about 2k with minimal electrical load. You should see about 14.5v, if you do then the alternator *is* charging so you have some time to consider what you want to do, although if it subsequently stops charging as well you won't know about it until the battery runs down. If you only see about 12v, of if the voltage rapidly drops to that level when you start switchig on loads like the headlights, then the alternator isn't charging properly and you have limited time before the battery runs down.

There are other causes for a glowing ignition warning light other than alternator failure, but if it is glowing at full brightness then it usually is the alternator, especially if it goes out altogether when the alternator is unplugged.
Paul Hunt 2

This thread was discussed between 27/10/2005 and 29/10/2005

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