Ignition warning light relay

one thing you should bear in mind, is that ignoring NOS, a new lucas alternator will be a Chinese reproduction quality can be variable, although to be fair lucas was never great!

Seem to have started something here! The alternators on evilbay are far east without doubt. However, we have fitted 3 or more on classic rally cars we build with no problems at all. These have been the old Lucas ACR pattern. Regards the question I posted many moons ago at the top of this post, we discovered the alternator was only turning out 1v at the warning light terminal, though the alternator charge rate is perfect. Mate of ours made up a gizmatroid to use one of the charging cables from the alternator to feed the ignition light relay which was checking out fine. When the engine is running the light gets its nominal 3-4v feed from the charging circuit via said gizmatroid and puts the ignition light out. Simples. At least we will now know if we drop a fan belt off.

still with the ignition warning light, even with the key out, the light is on, I have just fitted a new battery, as soon as I connect the leads, on comes the warning light?? Turn the key it goes out, any ideas welcomed
regards
Brian

First thought's is a faulty alternator , you are getting a back feed from it, so the current is flowing from the alternator through the bulb and earthed through all the circuits connected to the ignition switch. When you switch on the ignition there is then 12V at both the ignition and the alternator so the light goes out as no potential difference . Try unplugging the wiring connector at the alternator, & see if the light goes out. Is it an ACR type or 11AC alternator.