indicators issue

[Stag-Victor]

The last issue I'm trying to solve before I can obtain an MOT hopefully,

So the original symptom was a lazy left indicator, and I took the opportunity to install led indicator bulbs all round, and replaced the flasher unit with a suitable earthed unit.

This solved the lazy flash but now, with sidelights on, when I use the indicators, all four indicators will come on (albeit the side not 'signalling' is dim). This happens signalling both left and right.

By process of elimination of removing fuses for each lighting circuit I have narrowed the issue to the left hand sidelight circuit. However removing the side and tail light bulbs makes no difference.

Investigating the rear light cluster revealed a bit of a rats nest where someone had wired in a towbar, so have removed all that and am happy that the wiring there is now as it should be. Nothing is obviously wrong at the front sidelight. The instrument cluster lighting appears OK too.


I'm assuming power from the sidelight circuit is 'feeding back' into the indicator circuit somehow, but am running out of ideas as to how? The light clusters surely are the only point where the sidelight and indicator circuits meet? Has anyone come across a similar problem?

I havent ruled out the new indicator relay being the issue, but if so why would it work ok in all other circumstances?

thanks
Kevin

[v8ken]

if you have a dimming relay,LHS of boot behind carpet,next to rear nearside wing,might be worth by passing.

[jbuckl]

Could always try going back to non led bulbs?
Sometmes a flasher unit needs an amount of current draw to operate, that only resisted leds will provide.

[Stag-Victor]

Thanks, going back to non leds and the original flasher relay gives me my original problem of very lazy indicators on nearside; so doesnt solve the issue, but gives a different symptom.......And to note using a specific indicator relay for the led's

No sign of a dimming relay that I can see...

[Lingen]

Kevin.
What happens when you switch on the hazard lights? (or perhaps your's is an early car without them)
Mike.

[Stag-Victor]

Thanks, its an early mk2 without hazards

[Phil S]

Sounds more like an earth problem and the indicators are earthing back through the side lights. Is the flasher unit one suited to led's or just a standard 3 pin that needs an earth added? My leds were supplied with a suitable flasher unit .

[barkerwilliams]

Agree with Phil above poor earth problem on the bulb holders. Easy to test remove lens cover, get a length of wire and earth to engine block and hold the wire to the bulb holder problem should be corrected.
Then try and find the actual faulty joint - probably a bullet connector to the side & indicator light fitting.

Alan

[Stag-Victor]

Well, been out and had another, more productive session on this tonight.

Offside front indicator - previous owner had trapped the connector block behind the light cluster and screwed it down tight, crushing the connector. So connector replaced, didnt solve the issue but certainly needed attending to before it shorted out.....

Nearside front sidelight / indicator, the earth terminal had broken off the back of the light unit; so that would likely explain the slow flashing when using the standard bulbs

Night dimming relay was located, floating around in the depths of the inner wing (I assume it should have been attached!!), it appears these are not compatible with led bulbs, a quick test with the multimeter suggests it's sending 6v to the opposite indicator circuit when using the LED bulbs but not with the standard bulbs.


So thankyou all for the suggestions above, really helpful as always and fingers crossed I will have cracked it now!

Going to check over the rest of the wiring now, given the state of the lighting circuits.

[DJT]

Ditch the night-dimming relay. Just disconnecting the earth wire will disable it, but better to cut it out and splice the wires together. It is there to reduce the power to the stop lights and indicators when the sidelights are on. May have been a good idea 50 years ago, but not in the traffic of today.

[NeilR]

Even back in the 70's, that night dimmer was a silly idea.

[Stag-Victor]

Never even heard of one until now..... but yes entirely pointless and heading for the nearest bin!

[DZP]

It makes a good place to add an auxiliary fuse box.
Den

[jbuckl]

Are they all working now?
can you share the source of the new flasher unit with us please?

[fussydave]

My indicators behave in a strange way. They all worked as they should before I swapped to LED lamps Now with LED lamps fitted they flash very quickly. I changed the four indicator lamps to LED and fitted a flasher unit designed to work with LEDs and checked, all was well except for the faster flash speed. When I replaced the repeater side lamps for LEDs the indicators would not flash at all. I obtained a replacement flasher unit thinking it was faulty and this made no difference. I then bought another flasher unit designed for LEDs and rated at 30 watts, still they flashed at speed and if I fitted the LED side repeater lamps they would not flash. I have now left it with the standard side repeater lamps in and LED lamps to the main four lights. Despite the fast flashing speed It has passed the MOT three times since at two different MOT stations. Not sure why the side repeater lamps should cause the indicators to stop flashing, if it is a load issue I would have thought the lower wattage flasher unit would have compensated for this. If resistors are required to increase the load then this defeats the object of fitting LED lamps.

Dave