Brake warning light issue

[Silvestro]

Hi,
My first post! Hope you experts can enlighten me. Mine is a Mk2 Stag with the old electrical wiring where the Brake Warning light on the dashboard comes on with the oil pressure light in the cluster, ignition on, and they both go off as soon as the car is started.
Since I have replaced the oil pressure bulb in the cluster with a LED, the Brake Warning light doesn't light up anymore. Will I be able to solve this by replacing that one with a Led as well? If tha's the case, which led should I use to replace the original bulb?
If that doesn't do the trick, would I be right to assume that the Brake Warning light would still come on if the brake warning switch is activated?
Any suggestion would be welcome, Thanks.
Silvestro

[StagJonno]

Welcome.

I don't know if replacing the Brake Warning Light with an LED would solve your problem - can only suggest you suck it and see. It could be that different manufacturers use different LED drivers, which could behave differently. If you bought the cluster LEDs from Better Car Lighting or Classic Car LEDs, they could well be able to guide you. I have had dealings with Better car Lighting and Gil there has a very good understanding of the issues.

The Brake Warning light should still come on if the PWDA switch operates in anger - the circuit including the oil warning light is purely a test facility.

Have you also converted the IGN warning light to LED? If so, there could be issues with the alternator starting to charge - you'll get an idea of this with both the warning lamp and also the Voltmeter showing a low voltage - should get into the 14V range after a mile or so. The alternator is assisted in starting to charge by the small current that passes through the "normal" incandescent bulb. However, I'm told there's frequently enough residual magnetism in the alternator (particularly if you blip the accelerator) to get it started. I kept my IGN light as standard when I converted the other positions (mine has the later wiring which doesn't involve the Oil Press lamp in the test circuit for the PWDA).

[Phil S]

if your led's for the warning light cluster are from Gil at better car lighting then he would have supplied you with a resistor to ensure the alternator charges correctly

[Silvestro]

Thanks Guys for your suggestions. I bought the LEDs from ClassicCar LEDs and I send them an email as was suggested. Duncan replied almost straight away and, once I give him the right size and type of bulb (which I have just done), he will probably tell me which LED to use. To be honest, I've a feeling that will not solve the problem. I'll let you know. As for the IGN warning light, having read about the issue with LED, I've decided to keep the incandescent one.
Next job is to try and clean the glass on the speedo and rev. I have just taken the rev off the dashboard. Wish me luck!

[Silvestro]

here I am again. Problem solved. Duncan from ClassicCar LEDs sent me a replacement led bulb for the brake warning light. Now both lights work, although they flicker to the fuel pump ticking but that's ok. They go out as soon as I start the engine, as it should be. In case anybody should be interested here are the details of the bulb: BA7S 281 MCC LED DASHBOARD WARNING SWITCH BULB. Thanks again for your insights.