Night dimming relay

[Roger K]

1 hour ago, Colin Lindsay said:

That's one question that's been about for centuries - why do women with children in a pram always push the pram out into the road first?

We're really going OT here now, but seeing as I started the thread it's OK....

This was always one of my favourites:

 

[Colin Lindsay]

THAT will never be shown in the UK. It would just offend too many people - I mean, no way would you get a free parking space like that over here.

However the trailers at the end made my day... if only she'd been driving a Triumph, but she isn't so I'd pass on a loser like her.

 

[poppyman]

I am so offended by that.... I'm still laughing   Brilliant Roger...

Tony.

 

[Roger K]

It was never used, I think made just for fun.  Nice to know there are intelligent people still around, somewhere - it demonstrates VW's 'values' pretty well!

[poppyman]

54 minutes ago, Roger K said:

It was never used, I think made just for fun.  Nice to know there are intelligent people still around, somewhere - it demonstrates VW's 'values' pretty well!

Have a look at this, it's how things are getting.... 

[Martin V]

I bring this topic back to the original as it seems I just spent all my spare time over last three days trying to fix a problem that wasn’t there.

PO had fit one rear cluster, GT6 late model, incorrectly with dipped beam and brake connections reversed. On top of that Left was Right cluster and vice Versa. The latter had led to water ingress without drain slots on bottom edge. They do actually have a L and R on them! 
 

Anyway, stripped, cleaned, new gasket/sealant, tested each cluster in situ and all seamed fine. Went ahead and fitted both properly with all the 5 required nuts and spring washers ( not  that PO had managed either of these on rebuild).

Of course I then find that brake lights work great until I put dipped beam on. Then struggle to see the faint extra glow.

Went through everything like earthing both directly to body bolts instead of loom earth, cleaned and cleaned again contacts and the prongs that create the earth to housing. Swapped bulb holder for brake/dip left to right. All lights and indicators work great. Just brakes are faint when dipped are on but also seem to work properly on one brake/dipped beam if I disconnect the other cluster Red connector. 
 

I can see a bit of loom near pass side rear light where there are what look like the same colour wires bundled up and also what seems an additional loop possible joining a red end to red end. The other wires do not seem joined just cut and bundled. I’d guess this is the NDR removed but could it be that this bundle is still somehow having the same effect or is it that the NDR is still lurking hidden somewhere? Do I need to unpick the bundle and join the matching colours to each other as my brain suggests.

At least I have clean, dried lights and plastic lenses and when dip is off, I now have fully visible brake lights on both sides. To add to the upsides I now have a fuel tank/filler breather pipe fitted which takes fumes from filler vent to the hole in the floor rather than just venting into the car! Thanks again PO for that one.

 

advice on NDR appreciated please

Edited November 22, 2023 by Martin V

[Pete Lewis]

yes joining all like colours to each other is correct and dump the black earth

rear lamp problems with badly mixed claw holders with the mix of earthed claw /separate earth  single and twin filament bulbs and holders are often   a complete   mix up on Gt6 and Spitty

Pete

 

[Martin V]

5 hours ago, Pete Lewis said:

yes joining all like colours to each other is correct and dump the black earth

rear lamp problems with badly mixed claw holders with the mix of earthed claw /separate earth  single and twin filament bulbs and holders are often   a complete   mix up on Gt6 and Spitty

Pete

 

Thanks Pete, I unhooked all connections across the boot space and pulled the loom free to examine my little bundle. This turned out to be green/brown, some reverse light loop for some reason. I then went digging into that rear wing and found the Yellow (huge) relay box with all the wires attached. The culprit!

I've uploaded photos for future reference of anyone else finding the same issue.

I initially disconnected the earth as i think someone had suggested before, but then no lights worked.

I'll go ahead now and connect like colours to each other as per your message. Should the earth not be bolted to chassis?

 

Feeling relieved.

 

Edited November 23, 2023 by Martin V

[Pete Lewis]

not needed the earth is to complete the solenoid circuit in the relay 

the other end of the black wire will be already connected to a body earth somewhere 

Pete

 

[Alex Lowe]

I am having a similar issue with my rear lights but am at a loss where to progress next. 

My issue is my brake lights are not functioning when the rear lights are switched on obviously a bit of an issue for night time driving. However both seem to work independently of each other. So far I have done the following

I have by passed the dimming relay both by simply disconnection the earth and then joining same colours together. This leaves the black and red cables connected to nothing. 

I have cleaned both houses and bulb holders and tried multiple different ones of both. 

One observation I have noticed and cant quite work out is that when the bulb holders are removed from the light cluster and the brakes are applied the bulbs are lighting up. When I take a voltage reading of the red wire where it joins the front loom I am reading approximately 3V. I am not sure what's going on with this but does not seem correct. 

Any help or suggestions would be amazing as I'm pulling my hair out over this one. 

[Pete Lewis]

red wires are side lights  they must go to the side lamp bulbs 

these are twin filament stop/tail  and must have a claw holder with offset bayonet pins and two contacts

some claw need./have an earth wire  some rely on the claw earthing via the lamp housing being earthed

as said these all get mixed up and you get the results you are seeing 

so single contact and single bulb are indicator and reverse lamps  21w each

offset pin twin contact claw holder is stop/ tail 5w +21w

Pete

 

[Alex Lowe]

9 minutes ago, Pete Lewis said:

red wires are side lights  they must go to the side lamp bulbs 

these are twin filament stop/tail  and must have a claw holder with offset bayonet pins and two contacts

some claw need./have an earth wire  some rely on the claw earthing via the lamp housing being earthed

as said these all get mixed up and you get the results you are seeing 

so single contact and single bulb are indicator and reverse lamps  21w each

offset pin twin contact claw holder is stop/ tail 5w +21w

Pete

 

Hi Pete

 

Red wires are connected to the side lamp bulbs I was referring to the red cable into the dimming relay which does not have a second corresponding cable to join to like the others. 

I believe the holders are correct as they are both new from fitchett and I just double checked the bulbs wattage and they are 21/5W double filament bulbs. 

So I think this should rule out most of what you suggested?

For reference the car is a late MK3 GT6

[Peter Truman]

2 hours ago, Pete Lewis said:

 

 

some claw need./have an earth wire  some rely on the claw earthing via the lamp housing being earthed

as said these all get mixed up and you get the results you are seeing 

 

Pete

 

My Dolly Sprint had all sorts of earth issues with its rear tail lights, I started soldering earths onto all the push in bayonets, then a friend offered me some old saloon PI bayonets which had earth spade terminals fitted as standard made an interlinking earth cable seperately earthed to the body never another problem.

Triumph at some time and on some models used individually earthed push in bayonet bulb holders its just a matter of searching for them

[Martin V]

4 hours ago, Pete Lewis said:

not needed the earth is to complete the solenoid circuit in the relay 

the other end of the black wire will be already connected to a body earth somewhere 

Pete

 

Thanks Pete - all working perfectly now. Just as any normal thinking designer would wish. Brakes nice and bright even when lights are on.

@Alex Lowe my red connector to the relay was also just one connector but it did have two wires coming together into that singe connector. You can just see it on my pictures. I simply taped that over , did same with Earth connector and then used connectors to pair the ends of each of the three pairs together. Made a nice bundle and wrapped and protected it back where the relay was originally placed. Relay now in the spares box.

I also had all kinds of funny outputs as I progressed through cleaning with wet and dry all of the claws and rims of the holders where the claws need to contact for the earth. I also tried fitting earths to the chassis.

I'm assuming you checked that you do not have your connectors the wrong way around on the light/brake holder as one of mine originally gave a brighter light with lights on and then could hardly see the brake light effect. Worth double checking green purple goes to the brighter filament rather than the red lights connector.

Overall all though, if the brake and indicator are working and the brake / lights work all OK independently I concluded that the earth must be fine.

I hope you find the issue and get them sorted.

 

[SpitFire6]

25 minutes ago, Peter Truman said:

My Dolly Sprint had all sorts of earth issues with its rear tail lights, I started soldering earths onto all the push in bayonets, then a friend offered me some old saloon PI bayonets which had earth spade terminals fitted as standard made an interlinking earth cable seperately earthed to the body never another problem.

Triumph at some time and on some models used individually earthed push in bayonet bulb holders its just a matter of searching for them

I wish I knew of a supplier of quality 2 & 3-pin bulb holders. I have binned loads of single & dual pin holders over the years.
Getting low.
Cheers,

Iain.