donmacn

Member
Hi folks,
Hopefully I can't be the only one whose had issues like this...
I bought a set of LED lights (indicators, sides, stop/tail, reversing, fog and number plate) from Bolt on Bits. I'm not saying at this stage that there's any particular problem with the kit - I will email them directly and ask their advice - but maybe someone else here can provide some advice which will see me sorted sooner!

So, the side lights/stop lights work fine - front and rear, with the brake function OK. They give the car the extra lighting 'punch' I was after.

The number plate light, and reversing light just don't "light up" on the car. To check the lamps themselves, I connected them briefly across the battery - no bother, they work fine. So, I checked with a meter, and I'm getting about 7v for the number plate light and about 8.9v for the reversing light (both these initial meter readings then decline relatively quickly). I think the lights must just need more juice from the wiring loom. Any idea how I'd go about that?? Rewiring the whole rear wiring loom? If that's the case the old lights would definitely need to go back on for the medium term - feeble though they are. Unfortunately the reversing light didn't come off in one piece......

Indicators - this is more tricky. They all fit, and they all light up.... and that's the problem... they all light up, all the time. Indicating left? all four lights + wing repeaters flash. Indicating right? all four lights + repeaters. They do this whether or not I've put in the LED flashing relay which came with them, or the original one. The only difference being that the original one makes the lights flash much faster as the low current makes it think there's a bulb out.... I know these are popular kits, so as I say, I guess I'm puzzled that I haven't read about any other folk having similar problems.

THe car is a '94 Defender 110 SW.

Always grateful for any advice and assistance.

Cheers

D
 
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7V is a significant voltage drop (should be around 12V depending on battery state/condition, bit more than12V with engine running), my suspicion would a bad/loose connection somewhere.

Start off by checking your earth's on the rear left and rear right, indicators also give some weird and wonderful behaviour with bad earths so might be the same fault.

Next would be, with battery disconnected to bell out (continuity test) between the positive for the number plate lamp and where that cable comes off the fuse box.
 
First thing first, were all the lights working correctly before you started taking it apart? It is unlikely that every light you have bought is faulty so I suspect that they are not being connected up correctly.
Did you damage any of the connectors or disconnect any earths when you were pulling it all apart?
LED's are polarity sensitive so if you have the +VE & -VE reversed then they will not work.
 
LEDs are polarity sensitive so will not work if positive and negative are swopped.

Standard filament bulbs are not polarity sensitive.

LEDs require a minimum of 9 volts to work as standard.

Filament lights will just about 'glow' at low voltage.


Brendan
 
Hi
I had same problem fitted an adjustable relay and spun the wiring that wouldnt work on 2 of my indicators 1 fron 1 back opp sides now all working.
 
Thanks very much indeed for the replies guys, I'll try to respond to all the points logically.

All the original lights were working. The car got its MOT on Tuesday, and I had checked all the lights before taking it down. I guess I can't say 100% that they were still working today... but I do assume so.

As I say, I don't think any of the light units I've bought are faulty - they all light up fine. (Sorry, my OP was a bit long, but I don't think I said the units themselves were at fault). When the reverse and plate lights didn't light 'in situ', I rigged up short test cables and put the new LED lights directly across the vehicle battery - reversing lights and number plate light fired up fine. I had read that LEDs were polarity sensitive, so while I was pretty sure they were wired up OK, I did swap the wires just in case it made a difference, and it didn't. Because there is a current getting to their relevant circuits, I just assume it's not strong enough?

"Did you damage any of the connectors or disconnect any earths when you were pulling it all apart? " Don't think so - mainly a case of attaching crimp connectors. I've done this a lot, and I have the proper tools, so I'm pretty sure they're OK. One thing I haven't done (for the reverse and n. plate light) is to put the original units back to see if they still work. That's a useful thing to start with tomorrow. But as I say, I am still getting a current through the circuits when I expect to - i.e. when reverse is engaged..

So... for the reverse and plate lights:
  • "earths" are things to check - anyone know where the earths are for the reverse, plate and indicator circuits - somewhere close by, or back to the battery?
  • poor cable run between battery and lights. How would I do a continuity test on that? I have a meter, and a wee bit of experience, but electrics aren't a strong point.

Indicators:
Don't know where to start. They all light up fine, so the LED units are fine, and are clearly getting enough current. The fact that they all light up, when only one side is selected, suggests some sort of 'leakage' in the circuit, so that power is getting across to the 'undesired' ones...? (This happens with the adjustable relay, and without).
Again, I haven't put the originals in again to check they are still working, but that's now just four plugs to swap - easy done in the morning.

Thanks again.
 
I had the same issue with the indicators working at same time regardless of which side was needed the auto electrician done something to the actual indicator light behind dash panel....iv now got 2 small led bulbs in the dash to identify which way I'm indicating as he said there was a glitch with the dash bulb and the led ??
 
I had the same issue with the indicators working at same time regardless of which side was needed the auto electrician done something to the actual indicator light behind dash panel....iv now got 2 small led bulbs in the dash to identify which way I'm indicating as he said there was a glitch with the dash bulb and the led ??

Now, that makes some sense. Until you posted this I'd forgotten something I'd noticed earlier. When I put in the adjustable relay that came with the kit, and dial it in as per the instructions, I get a nice, bright trailer indicator in the dash until it gets "adjusted" to go out - but a very dim one for the indicators themselves (which might actually be an MOT issue..??) So, something more fundamental in the wiring behind the dash....

That's good and bad I guess. It confirms I'm not the only one who's had this, but without knowing just what to do behind the dash panel, it's maybe not an easy DIY fix tomorrow.

Thanks for that.
 
So... for the reverse and plate lights:
  • "earths" are things to check - anyone know where the earths are for the reverse, plate and indicator circuits - somewhere close by, or back to the battery?
  • poor cable run between battery and lights. How would I do a continuity test on that? I have a meter, and a wee bit of experience, but electrics aren't a strong point.

Indicators:
Don't know where to start. They all light up fine, so the LED units are fine, and are clearly getting enough current. The fact that they all light up, when only one side is selected, suggests some sort of 'leakage' in the circuit, so that power is getting across to the 'undesired' ones...? (This happens with the adjustable relay, and without).
Again, I haven't put the originals in again to check they are still working, but that's now just four plugs to swap - easy done in the morning.

Thanks again.

Earth points should be in the rear left and rear right corner of the tub I think, on the floor in the corners, or just trace the negative off one of your rear lights.

Continuity test, basically, select the symbol on your meter that looks like a a diode symbol or sideways wifi signal kinda of thing and touch your meter cables together. you should here a tone (you may have to press a button on your meter to select the tone option if its a fancy 'un). once you've got that working, you connect the meter to both ends of the cable you want to test, if you hear a tone then you have continuity, if you don't then the resistance in the cable is too high (ergo bad connection, broken cable etc).

Make sure the circuit you are testing is switched off.

For the indicators, they may well be related to the number plate issue, which is the easier of the 2 to diagnose so, if it was me, focus on the number plate light issue and the indicators may be fixed as result as well.
 
Earth points should be in the rear left and rear right corner of the tub I think, on the floor in the corners, or just trace the negative off one of your rear lights.

Continuity test, basically, select the symbol on your meter that looks like a a diode symbol or sideways wifi signal kinda of thing and touch your meter cables together. you should here a tone (you may have to press a button on your meter to select the tone option if its a fancy 'un). once you've got that working, you connect the meter to both ends of the cable you want to test, if you hear a tone then you have continuity, if you don't then the resistance in the cable is too high (ergo bad connection, broken cable etc).

Make sure the circuit you are testing is switched off.

For the indicators, they may well be related to the number plate issue, which is the easier of the 2 to diagnose so, if it was me, focus on the number plate light issue and the indicators may be fixed as result as well.

Cool, thanks. Just googled "continuity test." My meter doesn't have sound, but I do recall seeing the 'diode type' symbol. Every day's a school day. I'll see where that goes tomorrow.
I don't remember seeing an earth in either corner of the tub, so I'll try and trace that in daylight.

Started to consider a new loom for the back of the car. It's had 24 years of use and maybe abuse, and one chassis change... (rapidly approaching the second in January) so it might make sense just to do that anyway. It would be in keeping with my general approach to improve things as I go.
 
Now, that makes some sense. Until you posted this I'd forgotten something I'd noticed earlier. When I put in the adjustable relay that came with the kit, and dial it in as per the instructions, I get a nice, bright trailer indicator in the dash until it gets "adjusted" to go out - but a very dim one for the indicators themselves (which might actually be an MOT issue..??) So, something more fundamental in the wiring behind the dash....

That's good and bad I guess. It confirms I'm not the only one who's had this, but without knowing just what to do behind the dash panel, it's maybe not an easy DIY fix tomorrow.

Thanks for that.[/QUOTE
Yeah mine had to be altered as I could get the indicators to work by disconnecting the bulb from behind the dash .. but obviously this was a mot fail as I didn't know if the indicators were flashing ???...just try it to see if it's the same thing ...
 
Thanks again, If they all worked with the dash repeater bulb removed then that's a fairly easy thing to check.

In fact, thanks all. I've a decent list of things to play with tomorrow to try and take things forward. If I can't "sort it", at least I'll be able to try and eliminate a few things and pin down what might be happening.
 
Well, cleaning and greasing the terminals didn't do any harm... 5 minute job as the battery was exposed anyway.

But thanks for the advice to check the earths. I'd likely have got there myself, just more slowly. In daylight it was much more obvious - there was one three way bullit connector in a pretty bad way, and it was the one for the reversing and number plate lights. Remade that connection and all was well. Foglight worked fine too.

Indicators... the earth thing didn't sort that, so I removed the instrument console and took out the little repeater bulb, all the while thinking 'this surely isn't going to sort it'.... but it did. All the external indicators instantly started doing what they were supposed to! Thanks for that advice - I'd never have got to that one myself.

So, it's obviously not the bulb itself, but something about that circuit, which obviously serves both left and right indicators. Any further pointers on this? How did the auto electrician fix this? You said he put in separate dashboard repeaters for left and rigt indicators?? Did that mean changing the position of some of the dashboard lights, or getting new labels/icons??

Anyway, thanks for your help guys. The car is mobile again.
 
Have a search on here. There is current leakage across the dash bulb circuit. You can either sort it with resistors wired in series with the led units or fit a couple of diodes in the dash circuit.
 
Glad to hear you've managed to sort one issue and got a solution for the other.

Sounds like the flasher unit doesn't like LEDs, or rather LED's used with chassis return earths. *insert grumblings about chassis returns and robustness to fault conditions*

Out of curiosity, wouldn't an LED bulb in the dash also fix it (pure theory here) as it is in itself a diode?
 
Well, cleaning and greasing the terminals didn't do any harm... 5 minute job as the battery was exposed anyway.

But thanks for the advice to check the earths. I'd likely have got there myself, just more slowly. In daylight it was much more obvious - there was one three way bullit connector in a pretty bad way, and it was the one for the reversing and number plate lights. Remade that connection and all was well. Foglight worked fine too.

Indicators... the earth thing didn't sort that, so I removed the instrument console and took out the little repeater bulb, all the while thinking 'this surely isn't going to sort it'.... but it did. All the external indicators instantly started doing what they were supposed to! Thanks for that advice - I'd never have got to that one myself.

So, it's obviously not the bulb itself, but something about that circuit, which obviously serves both left and right indicators. Any further pointers on this? How did the auto electrician fix this? You said he put in separate dashboard repeaters for left and rigt indicators?? Did that mean changing the position of some of the dashboard lights, or getting new labels/icons??

Anyway, thanks for your help guys. The car is mobile again.
This is what the sparky done to mine ...not sure of how he done it though ???..if you look in top corners of the plastic binacle you can see the extra green lights ...hope this helps
 

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Thanks again folks.

The pic clearly shows that option, but I guess I'll try the 'bolt on bits' one - they seem pretty convinced about it, and its probably cheaper anyway than bringing in a sparky.

I guess their 'bulb' could be an LED too...?
 

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