LED indicator woes! HELP REQUIRED PLEASE - initial pics added to last post

[Andy Lef]

. com

Situation:

1.   I currently have SVC LED light blocks fitted to the rear of the car and halogen bulbs as indicators on the front.  All working as expected.

2.  I have an LED flasher unit fitted to the car to allow the Rear LED block to work.

3.  Brought a set of these and went about fitting them to the front - expecting there to be no problems - how wrong i was to be. 

4.  Tonight I fitted the new LED front indicators and the following happened.

• Four way / hazard flasher works fine with all four indicators going as expected;
• When either left or right indicator activated the following happens;
• Both rear indicators come on as well as the selected indicator at the front - in addition the not selected front indicator flickers in time with the selected indicator..

I have tried the following.

• changed the polarity of the front indicators which results in the front indicators not working whilst both rear indicators flash together.

 

I ran out of patience after 2200 hrs and the first gin.  Gin gone i stopped.

Struggling to understand the issue - very basic electrickery doesn't help.

All assistance welcome as I seek to get the car back on the road to make the most of the sun.

Andy

 

OK so additional info after a LR website and Youtube visit.  It could be either earth problems (LR websites) or it could be power leakage to the other LED lights (

.

Will try earth first as it's easier then look at Ballast resistors

comments welcome

 

[Jonathan Kay]

First thoughts about possible causes of that crosstalk:

1. The flasher unit is duff and it's happening within it.
2. The wiring at the flasher unit or indicator switch is wrong.
3. The wiring to the light units isn't correct.

So I'd try another flasher unit, probably a different type.

And if that didn't fix it I'd build the whole rig on the bench: lights, switches and flasher unit.

...

Do you have a multimeter? And more gin?

Jonathan

 

[Andy Lef]

Jonathan,

Thanks for your thoughts.

my comments against yours

The flasher unit is duff and it's happening within it. I have tried a different flasher unit here the red one is my current one and the black one arrived yesterday.  The black one doesn't seem to work (duff - not sure) the red one has been reliable and was working fine until the nre front LEDs were trialed
The wiring at the flasher unit or indicator switch is wrong. Not sure I can see how if it was working fine until i attached the new LED indicators
The wiring to the light units isn't correct. - Possibly and I considered that and changed the wires around in case this was the case .  When i did this the front indicators didn't work adn th rear indicators went into hazard mode even though only left or right was selected.

It's worth noting that the tail and brake LEDs work fine.

So I'd try another flasher unit, probably a different type. Did that but will do it again tomorrow as too many gins have been had and on a school night.

So no run to Blandford in the Caterham - Tin top it is.  and i may have to call a friend..................

[Blue C7]

First thing I would check is hazard sw they are notorious for giving different problems. Do you have a substitute to try.

[Jonathan Kay]

Agreed about their unreliability.

You could also disconnect it and see if the crosstalk between the indicators persists.

Jonathan

[JAL]

There are many flasher relays on the market and they are not all equal. The best for Caterhams to my knowledge is this one. Link

Doug

[Andy Lef]

Thanks all,

Doug, thank you. These flasher units are the two that I have and the black one (like your link) was to be the spare one, i tried it but it didn't seem to work (though that could have been me! - I'll try it again as it it only arrived a couple of days ago as a spare and shouldn't be broken (should it?).

Jonathan / Blue 7 I'll do the obvious with the Hazard switch as you recommend and see what happens.

Any thoughts on whether I need to re-wire the rear LED blocks at the same time to see if their wiring has an impact on the front LED wiring set up?

Andy

[Jonathan Kay]

Any thoughts on whether I need to re-wire the rear LED blocks at the same time to see if their wiring has an impact on the front LED wiring set up?

Common faults on rear lights are:

• Bad earth
• Bad internal connection
• False return through another light circuit.

Only the first of those is likely for you at the moment. And it wouldn't explain what you're seeing.

But temporarily disconnecting bits may be very helpful in debugging.

Jonathan

PS: Ordered the multimeter yet? :-)
 

[Andy Lef]

Jonathan

multi meter ordered - and how to book for dummies!

thank you.

 

 

[Blue C7]

Pain I know but can you easily reconnect the original indicators without actually fitting them to see if they still work ok

[Andy Lef]

Ah!  small problem with that - I was far too confident that all would work without a hitch (something you should never do if you own a caterham) and the original light fittings had bits pinging everywhere as I took them apart.  So sadly but also happily this is a none starter.

Earth checks tomorrow night - too many gins again!

 

[Andy Lef]

I have edited the first post with some fresh thoughts. 

 

How do I get the eye catching highlighted in yellow updated on the post title?

 

Andy

[Jonathan Kay]

I think it disappears after you've looked at the thread... and it might do the same trick as "New and Updated" and assume that the author has already seen it...

Jonathan

[Andy Lef]

So after lots of great advice and multi meter action (i have learned a lot).  it seems that, in my case, there is seemingly a simple answer.  I discovered, after trawling LR websites that people have had similar problems and it seems to be down to the dash indicator light, the original wiring has the indicators for each side of the indicators wired to the sides of the dash light, so when you indicate left the power is supplied to the left indicators as expected and goes to earth through the bulbs to light the indicators, power is also feed to the left side of the dash light, this powers the dash light going to earth via THE RIGHT INDICATORS, with normal bulbs not enough power goes to the indicators for them to actually light so all is fine. With LED's because they need so little power the right indicators will light.

I have found that by removing the bulb from the panel indicator light the LED lights all work as they should do. 

There seems to be 2 possible solutions:

1. Replace the old bulb with an LED replacement - i haven't tried this but have ordered the bulbs off ebay. It is also a fix that RDX seem to have produced for LR but with new wiring a LED bulb offered for £22 -  - I won't be going there.
    
2. The other option posited on a LR forum is to fix it by wiring each side to a different dash light, bit of a bodge but it would also seem to work.

So we wil wait fo the new LED bulbs to arrive and see if there is success. 

Andy 

[Jonathan Kay]

Well done. Fascinating.

It doesn't seem to have affected everyone who migrates to LED indicators, which might be due to differences in those resistances rather than the chosen flasher units.

So we wil wait fo the new LED bulbs to arrive and see if there is success. 

The D stands for... diode. I don't think that an ordinary LED will work both ways with your current wiring.

But you could rewire the indicator light circuit with an explicit earth and a diode in each side's shared connection to the other side of the lampholder... which is probably what that fix above does.

Jonathan

 

[Andy Lef]

Jonathan you may well be right since this is exactly what the RDX fix seems to do - here.

it's amazing what you learn when you have to fix your own problems (seemingly simple ones anyway!)

Andy

[SLR No.77]

Andy, my indicator dash light was already an LED version fitted prior to the LED Landrover units and has a diode fitted in each power feed to the bulb, your explanation has now enabled me to understand why there are two diodes. Simple fix will be as Jonathan has said, to add a diode each side of the dash light. It didn't occur to me that the dash light would have an effect when I provided the link to the indicator units!

Stu.

[Andy Lef]

Stu

Thanks, nice to hear I can help create greater understanding somewhere and not just feed off the experts on the forum. 

Also having just read this I now feel sufficiently emboldened to ask which diodes do we think i should we be looking at to create the desired effect.

Wiring  / soldering them in shouldn't be too difficult  , when upside down / legs over the roll bar and bleeding from banging my head on the steering column splines - again!  

 

Andy

[Jonathan Kay]

Do you want diodes that would work with the original incandescant lamp as well as the LED?

I'd make it on the bench with connectors that make it easy to fit and revert... but I look forward to the photos! :-)

Jonathan

PS: "... feed... "... nearly missed that one.

[Andy Lef]

Jonathan

Probably just to work with the LED that's coming or is there a middle ground diode that works with both (if the LED doesn't work). 

If i can find enough spare wire behind my dash I'll try and fix the diodes up so that if they 'burn out' they are easily replaceable 'ish.

I'll try and remember the pictures!

[Roger Ford]

Diodes will cause a small voltage drop (in the "right" direction) so your dash light will likely be slightly dimmer. Zener diodes typically drop 1V - if that's too much you need to look for a Shottky diode.

I reckon these Zeners should be quite suitable - get the 20v option. 10 for a quid delivered.

[Drumster]

Andy,

You need to convert your scuttle to a removable one, best thing I ever did for tinkering behind the dash 

[Andy Lef]

Roger, Many thanks now ordered.

Aeroscreens hi,

Sounds like an interesting winter project - have you got any build notes or pics for this?

Andy

[Drumster]

Andy, as it happens my scuttle is off at the moment so will take pictures tonight hopefully and post on here with a few comments

[Andy Lef]

Brilliant many thanks!