LED indicators

[jik22]

OK, I'm stumped. I've been converting my lamps all over to LED, and all was going well until the indicators. I bought a new flasher relay which is supposed to work with the low current LED's instead of the 21w bulbs, and the relay works to the point all the other flasher bulbs not yet replaced do flash, but no matter what I do, I can't get the LED bulbs to flash! :(

LED flashers themselves are fine, as they light with a 12v source put across them.

[ladas]

The only thing I can think of is, LED can only be wired in one direction unlike other normal globes - so if the polarity is reversed ?

Just a thought.

[jik22]

The only thing I can think of is, LED can only be wired in one direction unlike other normal globes - so if the polarity is reversed ?

Just a thought.

Yeah, but on the indicator bulbs, the surround is always ground and the solder blob on the middle of the bottom of the bulb is positive...so unless my cars always been wired wrong....

I should also add I don't think it is a load issue, as I can leave all working lamps in circuit and add the LED ones in parallel to the front indicators and all the rest continue to flash while the LED one doesn't.

Also, if I use a bench power supply to quickly turn the supply on and off with the LED lamp connected, it does flash as it would in an indicator.

So, what am I missing? :confused:

[dmdigital]

It almost sounds like the relay isn't actually suited to the LED lights. Have you tried using the relay on the bench with an LED indicator lamp rigged up?

[jik22]

It almost sounds like the relay isn't actually suited to the LED lights. Have you tried using the relay on the bench with an LED indicator lamp rigged up?

I haven't, but it is marked as (And bought speficially as) being an LED relay! :(

Been Googling for ages trying to find out how the LED ones work...as my new one also clicks like the old bi-metallic strip Lucas one did, so I can only assume it has a load resistor in it somewhere, whereas I was expecting them to be all electronic these days??

The bit I really don't get is why, when all flashers on one side are working, and I just put the LED across one set of the indicator wires so it gets the same feed is why it still doesn't light!

Will probably end up buying another just to test, which is a pain.

[langy]

I've had this happen to me.. sometimes the wiring does get a bit mixed up -even in the factory. Use some spare wire to test what happens when the leads on a blinker are swapped over and try the led's again. You might find that to make them work you will have to swap pos to neg

[jik22]

I've had this happen to me.. sometimes the wiring does get a bit mixed up -even in the factory. Use some spare wire to test what happens when the leads on a blinker are swapped over and try the led's again. You might find that to make them work you will have to swap pos to neg

Well, turns out you and Ladas were spot on. The bloody things are wired so that the metal case of the bulb is getting +ve and the centre contact is -ve.

Now I have the lovely job of rewiring all the connectors...and I bet the things are one-time insertion only too. Grr....

Anyway, thanks both for the hint.

[dmdigital]

Jeff is this the Defender or the D3?

[jik22]

Jeff is this the Defender or the D3?

Defender. I'm not allowed to touch the D3, as it's "hers" apparently. :D

[scrambler]

Well, turns out you and Ladas were spot on. The bloody things are wired so that the metal case of the bulb is getting +ve and the centre contact is -ve.

Now I have the lovely job of rewiring all the connectors...and I bet the things are one-time insertion only too. Grr....

Anyway, thanks both for the hint.
Assuming the wiring is similar to the older ones, I'd think of exposing the wires inside the front wheel arch, cutting and swapping over with good crimping connectors, slipping a heat shrink tube over at the same time to close the gap in the insulation.

Alternatively, and if you're lucky, you might be able to swap the leads wherever it is they attach to the loom. Can't speak for anything later, but my Series III had an earth problem in the indicator today, and the wires attach to the loom to the right of the radiator. Worth having a look anyway - might save cutting anything.

[jik22]

Assuming the wiring is similar to the older ones, I'd think of exposing the wires inside the front wheel arch, cutting and swapping over with good crimping connectors, slipping a heat shrink tube over at the same time to close the gap in the insulation.


My '94 is the first of the new style one piece light fittings where the bulb assembly twists off the lamp from the back, and connects to the loom with a clip on connector. I used these when fitting the NAS style rear fog and reversing lamp, but I have no idea if you can get the crimps out of the connector a second time to reverse them - will have a go later today.