Brake Light Question

[Grants]

It seems the inside brake light on US cars has a bulb in it so you actually have 4 brake lights across the back plus the 3 small bulbs on the hatch? Is this right? The inside light on the Eunos 30X just has a plug in the bottom where the lampholder would fit so we only have 2 brake lights plus the one on the hatch.

Now, if a brake light bulb blows, a red warning light coes on the dash saying "brake".

So does anyone know what effect it would make if I put lampholders and bulbs in the spare socket in the taillights? It seems it would affect the operation of the warning light but exactly how I don't know. Maybe then the warning light would only operate if I blow 3 bulbs, or maybe I could burn something out by having the extra load on the circuit? Maybe I should put in LED bulbs?

If anyone knows anything about this it would be appreciated.

[Taras]

Usually 'bulb-out' features run on a load dependent basis. If a circuit detects a drop in load, like a burned bulb or LED's, it will notify you. By adding extra bulbs, you increase the load on the system. Depending on the set-up of the factory wiring, you may have to loose 3 bulbs as you said to activate the bulb-out warning.
Cheers.

[Grants]

Thanks, I'd sort of assumed that would have to be the case.

You can't see that adding the extra load of a couple of bulbs may damage the circuit? It seems quite sensitive as it even picks up one of the 5 watt lamps in the hatch.

I could probably bypass the problem by putting in LEDs but my only concern there is the illumination may be quite different to the standard bulbs and that would look weird. If it does I'll have just thrown away $40. I haven't seen the LED bulbs in operation.

[perhapsadingo8yerbaby]

Originally posted by Grants:
...You can't see that adding the extra load of a couple of bulbs may damage the circuit? It seems quite sensitive as it even picks up one of the 5 watt lamps in the hatch. I could probably bypass the problem by putting in LEDs but my only concern there is the illumination may be quite different to the standard bulbs and that would look weird. If it does I'll have just thrown away $40. I haven't seen the LED bulbs in operation.

I wanted to put in LEDs to reduce elec demand but dropped the idea when finding that all the LEDs I could locate were oriented wrong for the MX-3 tail lights. The LEDs offered had the lights at the end of the bulb so would need horizontal mounting to be seen well. The MX-3 bulbs all mount vertically so LEDs would be pointed upward in the lens housing instead of outward.

Did you see some LEDs that had a bulb shape to orient the lamp end at 90 degrees from a vertical mount position?

[Grants]

Thats a good point - I have only seen the bulbs in auto shops and the orientation of them hadn't crossed my mind! They'd look like siht, especially next to the existing ones.

I think you just saved me from wasting $40. I'll check what are available, but the more I think about it the more I know you're right

[perhapsadingo8yerbaby]

I just Google'd for "90 degree LED" and this was one of the sites that came up. http://www.superbrightleds.com/1157.htm Scroll 1/2 way down for the 90 degree ones. Might be worth a try...

<small>[ November 11, 2004, 05:41 AM: Message edited by: perhapsadingo8yerbaby ]</small>

[Grants]

Hmmm... they'd need to point directly backwards (or forwards into the reflector?). I just looked at a lampholder and the bulb position isn't adjustable so it could end up pointing in any direction.

Thanks for your help, I think I'll stick with a standard filament bulb and see what happens with the warning light.

[perhapsadingo8yerbaby]

Yeah, I'll stick with stock filament bulbs for now too although I'd bet the 90 degree type LEDs would face directly back/outwards cause otherwise, why make em...

[Grants]

I installed the 3rd and 4th brake lights using ordinary bulbs.

I was concerned the bulb-out feature may light up with the extra load on the circuit but this isn't the case. I assume though the bulb-out doesn't work as intended any more with the 2 extra lamps.

I'm not sure which spec cars use these 3rd and 4th brake lights but if you haven't got them they're well worth installing.