S2 rear indicator failed and LED flashing instead

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dewarcraig
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S2 rear indicator failed and LED flashing instead

Post by dewarcraig » Fri Feb 20, 2015 10:50 pm

Guys, I'm after a bit of help please. I was out in my 07 exige tonight and when I put the right indicator on I noticed the dash indicator flashing really fast. Inspection outside the car shows that the right rear indicator has stopped working and the red LED light is flashing instead.

The other side of the car works fine and I swapped over the indicator bulbs with one another and proved that both bulbs are ok.

Can anyone help with what might be the issue or suggest where to start and I'll carry on my fault finding in the morning when it's light :(

Thanks in advance guys!!

Craig.

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robin
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Re: S2 rear indicator failed and LED flashing instead

Post by robin » Sat Feb 21, 2015 8:34 am

Bad earth is the normal cause of disco lights, though I am surprised that it happens with LED lights (a normal bulb will light up whichever way round you connect it to the battery; a LED will only light the right way round; a bad earth fault relies on conducting backwards through one of the bulbs).

Anyway, I would still be looking for a wiring fault at the light cluster or a connector near there.

Cheers,
Robin
I is in your loomz nibblin ur wirez
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dewarcraig
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Re: S2 rear indicator failed and LED flashing instead

Post by dewarcraig » Sat Feb 21, 2015 9:13 am

Thank you Robin. I agree that it seems odd with the LED lights and the fact that the LED ring has changed function and become an indicator instead, but perhaps this is normal if no load is being driven through the filament indicator bulb as a safety feature to still indicate of sorts?

As I say, I'll have a look in more detail this morning. I did have the boot carpet and foam out last night and the seats, tunnel out last weekend, so here's hoping that I've just disturbed a connector. I'll start at the rear cluster connections and presume there's a connector in the boot. I also believe that thees a connector in behind the rear arch liner. Where else?

Any other suggestions?

dewarcraig
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Re: S2 rear indicator failed and LED flashing instead

Post by dewarcraig » Sat Feb 21, 2015 1:51 pm

Ok, new development!! I had a look this morning and did the following -

Firstly I wiggled the wires and connectors on the offending side - no change.
Next I split the connectors Found some corrosion in the offending side clip and cleaned it up with a screwdriver and electrical cleaner. Re assembled and tested - no change.
I then swapped over the light units and the fault remained on the same side - so not the light fitting.
Next I tried swapping over the short light harness from one side to the other - now both sides don't indicate, even when I swap the harnesses back and forth... Grrrr!

The short light harnesses look identical so I doubt that swapping them has directly stopped the good one from working. The only possible conclusion I draw is that the fault is coming from the car and has broken both of the short light harnesses that have been plugged into that side as I notice that there are electrical components under the black heat shrink.

I'm fairly handy with electrical items, so happy to do some more testing and fault finding if someone can give me some pointers or electrical drawings (or both! :) )

Any help is welcomed!! Or else it's going to have to be another trip to Murrays :(

Thanks.

P.S - I tried unplugging everything and confirming the light units and short harnesses are back in their original places and all connections are good and something slightly different appeared to happen, the left indicator worked ok for about 3 clicks then stopped all together and the dash indicator flashed/clicked fast again. For completeness I also turned on the lights and confirmed that both rear LED rings operate, but only the right hand side LED ring flashes when I put the indicator on, the left just remains lit.

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robin
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Re: S2 rear indicator failed and LED flashing instead

Post by robin » Sun Feb 22, 2015 10:50 am

You may have to identify which wires in the connectors are which. Then unplug the loom and measure the resistance from the earth back to the battery -ve and the live back to the battery +ve when the ignition is on. Usually the indicators would be switched live, permanent earth - but given the Lotus is plastic and so does not have a natural common earth, it might be switched earth, permanent live (unlikely).

Also using two wires connected to the battery (e.g. a long strip of mains cable), you can test out each bulb by connecting up live and earth to each bulb in turn. Be careful - you might break the LED lights if you connect them up backwards - so this only works if you have a clear idea of which cable does what. You can then plug in the short loom and check it again, etc.

Eventually you will determine where the open circuit is. My money is still on a corroded or loose earth point somewhere.

Cheers,
Robin
I is in your loomz nibblin ur wirez
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a4drk
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Re: S2 rear indicator failed and LED flashing instead

Post by a4drk » Sun Feb 22, 2015 8:05 pm

One of my outer LED lights (side lights) has gone really dim - almost out

Knackered light fitting ?

David
Two negatives make a positive but only in Scotland do two positives make a negative - 'Aye right.'

S2 Exige
BMW 435d M Sport - 375bhp..... and stops now (big brakes!😁)
Work Horse - Ford Transit - Full of crap spec....... 170bhp one :-)

dewarcraig
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Re: S2 rear indicator failed and LED flashing instead

Post by dewarcraig » Thu Feb 26, 2015 12:01 am

Hopefully the final update on this issue...

Decided to contact Craig at Murray's, who as true to form did his best to get me in asap. This afternoons visit lasted long enough for me to shake hands, drink a complimentary cuppa, explain the issue to the technician, say thanks and leave a happy customer... (About 15 mins!)

Turns out that at some point someone has decided to fit an interconnecting plug in harness (non Lotus) to each of the rear lights. It's thought that these are intended to be used on cars converting between filament and LED rear lights. Not really sure how my car has ended up with these as it came from the factory with LEDs. I'm not sure how long these parts must have been installed for, but they certainly worked for a good while of my ownership before causing some very strange behaviour and inconsistent fault finding.

All sorted now and the two offending articles thrown in the bin! Massive thanks to Craig and Murray Lotus for their help. I'm not sure how long it would of taken me to work out that these connectors shouldn't of been there, they looked OEM enough after all.

Anyways, an easy fix in the end. Thanks for your input as well Robin, much appreciated.

Craig.

dewarcraig
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Re: S2 rear indicator failed and LED flashing instead

Post by dewarcraig » Thu Feb 26, 2015 12:05 am

A4drk - yes, it sounds like some of your LEDs are starting to fail. It is possible to replace these if you are fairly handy, have a lot of patience and take your time to split the moulded plastic fitting and solder in some new LEDs. Or replace the light unit for £175-ish and a 10 min job. You pays your money... And all that :)

Craig.

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a4drk
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Re: S2 rear indicator failed and LED flashing instead

Post by a4drk » Thu Feb 26, 2015 9:38 pm

Where do you buy the LEDs ?
Maplins ?


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Two negatives make a positive but only in Scotland do two positives make a negative - 'Aye right.'

S2 Exige
BMW 435d M Sport - 375bhp..... and stops now (big brakes!😁)
Work Horse - Ford Transit - Full of crap spec....... 170bhp one :-)

dewarcraig
Posts: 43
Joined: Sun Aug 10, 2014 10:20 pm

Re: S2 rear indicator failed and LED flashing instead

Post by dewarcraig » Sat Feb 28, 2015 7:47 pm

I got mine from mouser electronics. Think they're in the states. I'll dig out the details for you if you'd like. They appear to be a perfect match too :)

Craig

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campbell
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Re: S2 rear indicator failed and LED flashing instead

Post by campbell » Sat Feb 28, 2015 8:45 pm

Craig - priceless!

Murray Lotus in unplugging unnecessary wires shocker, LOL.
http://www.rathmhor.com | Coaching, training, consultancy

dewarcraig
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Re: S2 rear indicator failed and LED flashing instead

Post by dewarcraig » Sat Feb 28, 2015 8:53 pm

Oh mate, I know! Thing is, I'd never have known unless I compared directly to another exige of the same year and even then I'd be sceptical trying it in fear of popping something since the resistors were clearly changing power requirements!!

Exige 1, Craig 0 :cheers

Craig.

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campbell
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Re: S2 rear indicator failed and LED flashing instead

Post by campbell » Sat Feb 28, 2015 10:25 pm

These Lotuses are getting complex these days.

Long live the Elise S1 :-)
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