LED wiring

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gymmaniac

Well-Known Member
Posts
615
Location
Bedfordshire
Hi,
Just upgrading the lights to LED. main lights fine. drivers side fine. Rear indicator and brake lights not so fine.

Eventually worked out that the polarity is wrong.

indicator was an easy fix as i just swapped the two wires around at the connector end.

The brake light is a bit more messy as the tail light part works with the lights being turned on but the brake light doesn't come on....

anyone got an easy fix before my brain explodes.

It's a defender 98 plate about when the wiring all swapped over, given the general other problems I've had i think mine was put together while the parts bin was emptied of spares.
Thanks

Andy
 
Just keep swapping the wires til it works?
Seriously, if the tail is illuminated as should be, but no brake lights, it's possible that you're putting you're 12v+ in the correct way but earthing through the brake led, or what you're seeing is actually the brake led and you're tail leds are linked to the brake system meaning you won't notice them because you've already got full brightness.
 
Yes, maybe use a meter or test bulb and see which of the three becomes live when you switch the lights on, which one comes on if you rest an old brick on the brake pedal and which is left over.
In case you've got a duff lamp unit try it on the other side where you know you've got it sorted. Or try the known good one on the problem side. I had a little adjustment of this kind to do when I put my LEDs on, but it sorted itself out eventually.
 
If I can remember, when I did the change to LEDs on my Disco 2 I had to change over the wiring for almost all of the single filament bulbs but the wiring for the stop/tail lights was already correct.
The negative or earth wire should connect to the body of the bulb and the tail lights to one of the two pips and the stop lights to the other pip.
The way mine work is on tail lights only all of the LED chips illuminate, as they do for the stop lights with the tail lights off. When the stop lights come on while the tail lights are illuminated the light output level brightens quite a lot.
 
I have a theory about this, which probably shows my level of electronic competence!!

I didn't buy 'proper' :LED lights, but started to swap bulbs. Fronts were fine, rears said no chance. Followed everything through and no apparent issues anywhere so I started to re-make connections to find that a lot of the wiring was somewhat blackened, and not making good connections. (1989 vehicle) After redoing connections and substituting black for good copper wire all was well. So my theory goes that normal lights run at a certain current/resistance which is (complete guess) somewhat higher than an LED and when LED bulbs are put in then the system just says **** off, we ain't accepting such a low current/resistance as valid and won't bother lighting up any lights. Just a theory ... I also found that LED's are somewhat vulnerable to polarity changes ...
 
I have a theory about this, which probably shows my level of electronic competence!!

I didn't buy 'proper' :LED lights, but started to swap bulbs. Fronts were fine, rears said no chance. Followed everything through and no apparent issues anywhere so I started to re-make connections to find that a lot of the wiring was somewhat blackened, and not making good connections. (1989 vehicle) After redoing connections and substituting black for good copper wire all was well. So my theory goes that normal lights run at a certain current/resistance which is (complete guess) somewhat higher than an LED and when LED bulbs are put in then the system just says **** off, we ain't accepting such a low current/resistance as valid and won't bother lighting up any lights. Just a theory ... I also found that LED's are somewhat vulnerable to polarity changes ...
There aren't many stories on here or anywhere else where somebody says 'n I turned the key and tried all the lights and everything worked perfectly straight away and has ever since' which is why despite saving up for 18 months to buy a full set of led lights I didn't bother.
 
There aren't many stories on here or anywhere else where somebody says 'n I turned the key and tried all the lights and everything worked perfectly straight away and has ever since' which is why despite saving up for 18 months to buy a full set of led lights I didn't bother.

Wouldn't it be a boring world if everybody just "turned the key and tried all the lights and everything worked perfectly straight away and has ever since"?
 
so having, fit connectors, proved no fuses blown with the old lamp and generally fiddled it now works exactly as it should have done the first time.......
 
Hi,
Just upgrading the lights to LED. main lights fine. drivers side fine. Rear indicator and brake lights not so fine.

Eventually worked out that the polarity is wrong.

indicator was an easy fix as i just swapped the two wires around at the connector end.

The brake light is a bit more messy as the tail light part works with the lights being turned on but the brake light doesn't come on....

anyone got an easy fix before my brain explodes.

It's a defender 98 plate about when the wiring all swapped over, given the general other problems I've had i think mine was put together while the parts bin was emptied of spares.
Thanks

Andy


You are fitting LED BULBS to existing wiring and lampholders and not LED light fittings right?

Led Bulbs need to be 12v 21/5w OSP BAY15d Brake & Tail

Following could explain why you are having trouble.
LED versions of the brake and tail have two positive connections at the base, the lamp holder has two corresponding connectors for original lamps, they have offset pins so you can only fit it in one way ( see pic below)
LED bulbs often do not have pins in the correct place, so try rotating the led bulb through 180 degrees Also Led bulbs unless they were expensive they tend to be poorly manufactured, thus the twin contacts on the bottom don't always line up!
(cheap leds have round blobs better ones have oval strips)

My bet is its just mis-aligned connectors on the bottom.

Side wall of the bulb is negative, the blobs on the bottom are positive.
If your old filament bulbs work ok, then led ones will too just have to make sure the bulb holder polarity is correct.
If the polarity is reversed the old filiament bulbs would still work fine.
However the leds will not! (pic below to show bulb holder(non LR).

LED bulbs are not all the same, two main types
1) just get brighter on stop
2) additional section lights up brighter on stop

So with type one its hard to tell if you are on tail or stop!



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The led bulbs I used were same as normal on the base, with a cluster of leds around a central column where the normal bulb would be.
 
I had a similar problem when getting fed up with changing normal bulbs every few months.
I got a set off ebay for all indicators and stop n tail. After fitting an LED turney on and offy thing for the indicators all was fine but I couldnt get the stop n tail to work.

Back on the bench I found the two dobs of solder (sarder, if merkin) on the back of the lamp did the same thing. No extra brightness at all when the second circuit was opened. Tested it all ways but thought both wuz duff.

Turns out they wuz stop 'or' tail lights not stop and tail. Something the Chinese had not made very clear. The seller sent me some different ones with a type of glass lens on the end. Those worked great although the brake light wasnt very much brighter than the tail. I fitted a light bar over the rear door to make sure.

New ones that didnt work.........................

s-l500.jpg


Cant find a pic of the replacements that did work..........................
 
Mine were similar to @Bobsticle s but with more leds, maybe 6 stacks ... From banggood, very cheap, like £5 for 5 pairs .... a couple of years ago so dunno what they'll be now .. :)
 
If you want to use led bulbs in vehicles, make sure they are 'COB' (chip on board) type. COB's are classed as SMD (surface mounted device).
Much more reliable and stable than the older 'through hole' LED's.

As usual ebay+china+electronics = 'bag-0-sheet" rubbish that if it is one piece when it arrives it wont be for long.

Ring do some good COB ones in UK, and CANBUS compliant so no MIL lights on dash etc if you have a posh LR.The usual 'get what you pay for' comes into play!

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Best option by far is a replica LR lenses with built in LEDs, brighter, safer and totally reliable.

Like these PS beware the Similar wipc jobs, IMO they look crap but aside from the thier relay is useless and non tuneable, and the light units leak!


GOOD ONES :
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Why fit load resistors they defeat the whole object of less power. ?

A Standard Flasher Relay works on load, this means it is designed to see 21 watts bulbs, when you fit LED lamps or bulbs the Relay can not detect the load as the LED lamp/LED bulb may only use 2 to 3 watts, resulting in fast flashing which is no good to anyone. (WICRAP)

So people fitted load resistors to imitate the load of the incandescent bulbs they have just removed, resulting in more wiring, things that get hot, melt anything near them and the best bit you are using more power than a standard bulb set up!

Then came LED Flasher Relays

These often only could handle 30 to 40 watts which is fine for all LED vehicles but as soon as you put a trailer on it would blow or the user would fit the relay with bulbs and blow the LED Flasher Relay.

Some have tried to create a 4 Pin Flasher Relay but they state it might put the trailer light on when you are not pulling a trailer plus it can only handle 40 watts rdx relay can handle 140 watts.

WIPAC attempted to copy RDX Relay but failed all they could do was adjust the flash rate, it puts the trailer light on when you are not even pulling a trailer.

RDX 4 Pin Flasher Relay can handle bulbs, LEDs and a mixture of both on the vehicle.

Tuneable this means it can be adjusted to suit your vehicle by simply turning the adjustment knob on top of the RDX 4 Pin Flasher Relay.

MOT law changed resulting in the trailer light must flash when a trailer is connected and the indicators/hazard is used. The MOT station can now test the towing socket if fitted!

Other Flasher Relays including the WIPAC LED Flasher Relay cannot detect a trailer has been connected which is now a requirement.

The trailer must be using incandescent bulbs or LED lamps with load resistors for the Trailer light to flash. It cannot detect trailers solely on LED lamps it will make them flash ok but will not flash the trailer light as the extra load is too little to detect.

You pays yer money you takes yer choice!

Its not often something just works and does what it should, I am very happy with it.
 
Replace a standard filament bulb with a LED bulb and immediately your vehicle is not road legal!

The only legal way to get LED lights all around is to replace the complete light unit for a LED unit with the correct approval markings on.

Look on the back of the blister cards on LED bulbs in Halfords for OFFROAD USE ONLY.

Look on the Ring website OFFROAD USE ONLY


Brendan
 
Why fit load resistors they defeat the whole object of less power. ?
There are some flasher circuits such as that in the Discovery 2 where the flash rate is actually set by electronic components which drive the appropriate relays instead of the thermally calibrated type in older vehicles. There's no way to fit such a "LED relay".
MOT law changed resulting in the trailer light must flash when a trailer is connected and the indicators/hazard is used. The MOT station can now test the towing socket if fitted!
The 13 way towing socket is part of the MoT, the 7 way 12N type isn't.
 
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