LED ignition warning light

[Babord]

I have read about battery charging issues when replacing the ignition warning light with an LED bulb. With the engine running, when the ignition light goes off, does it always mean the alternator is charging OK (assuming alternator itself is in good condition)? After fitting an LED and starting my car the light is on, but goes out as soon as I tap the throttle. Can I assume all is good, or are there still potential charging issues to be aware of with an LED?

[mallardstag]

If the volt meter shows 14-14.5V then all is good. Also check voltage when idling after start before pressing the throttle, this is when the LED may not work correctly and the alternator won't produce current until you increase the revs. You can get around the problem by adding a 3W 150ohm resistor across the led.

[StagJonno]

I kept my IGN warning light as incanescent. Ocassionally it stays on after starting and needs a blip to ~2,000rpm, then all's well. As MallardStag says, see what your voltmeter reads, after a couple of minutes - it takes time to respond being a thermal-type.

[Babord]

Volt meter gauge was reading 12.5 ignition on, rising to 13.5 engine running. Replaced the LED IGN with original bulb, and exactly the same. So hoping all is good and gauge just reads a bit low?
Anyway, I decided to leave the original bulb in place. Only really need LED for the indicators and choke.

Also fitted LED headlights (warm white) into new Lucas bowls to replace my old sealed beams. Wow, what a difference!!
oh, and very pleased to find tip on the forum to use pieces of plastic to keep screws in place when re-fitting the grills - so much easier!

[Bakdraft007]

Volt meter gauge was reading 12.5 ignition on, rising to 13.5 engine running. Replaced the LED IGN with original bulb, and exactly the same. So hoping all is good and gauge just reads a bit low?
Anyway, I decided to leave the original bulb in place. Only really need LED for the indicators and choke.

Also fitted LED headlights (warm white) into new Lucas bowls to replace my old sealed beams. Wow, what a difference!!
oh, and very pleased to find tip on the forum to use pieces of plastic to keep screws in place when re-fitting the grills - so much easier!

Is she a Mk1 or Mk2? The Mk1 has a 16RA which has a excitation resistor built onto the back of it, so there should be no need for a parallel resistor. That said, I ended up doing the same as you and fitted a normal bulb for the ign as the LED made my Mk1 misbehave. Its the only bulb on the car thats notan LED. OK thats not quite true as I changed the headlamps to H4's which are plenty bright enough, and as I drive her in the dark only once or twice a year its fine.

[Babord]

Mk2, and I am happy to keep the normal IGN bulb.
I live in a rural area with no street lights, and H4/H1s would have been fine, but as I had sealed beams and needed to buy new reflectors I thought I would try LEDs at the same, and I like that they draw less.