Rear lights gone crazy

Juve

Active Member
Feb 9, 2014
23
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Hey guys,

I was wondering if any of you have come across this before.
Last night all my rear lights have gone completely crazy.

I was at a turn, signal on when suddenly it started blinking faster and the rear fog light came on the dash. I thought - alright I blew a bulb.

When I got home I found that all the lights on the back have gone crazy. When I put the turn signal on the back lights blink dimly, when I press the brakes the turn lights come on, reversing lights do no work and all kinds of combinations of the above.

I checked all the lights, bulbs, fuses everything seems fine. All other electrics on the car work fine and the fron lights, turn signals everything work just fine.

I noticed that if I have the hazard lights on and I open the boot lid the interior boot light blinks as well :cry:

Any thoughts would be appreciated.

Cheers
 

waynedunn1234

Active Member
Aug 23, 2013
56
0
sounds like a earth problem, when i was younger on a cinquecento the rear brake light blew one of the 2 stage bulb. double check this as i had alsorts of problems ( when i pressed the brake pedal would flash the head lights lol
 

Juve

Active Member
Feb 9, 2014
23
0
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I thought of a ground cable. Any idea where they are on the back of a leon MK1. I believe there is one below one of the clusters (passenger side)?
 

waynedunn1234

Active Member
Aug 23, 2013
56
0
I thought of a ground cable. Any idea where they are on the back of a leon MK1. I believe there is one below one of the clusters (passenger side)?

im not sure of the location. also the problem could be water getting in the rear end and shorting something out. i would investigate the boot area
 

Juve

Active Member
Feb 9, 2014
23
0
Reading
sounds like a earth problem, when i was younger on a cinquecento the rear brake light blew one of the 2 stage bulb. double check this as i had alsorts of problems ( when i pressed the brake pedal would flash the head lights lol

i checked the bulbs, they look fine. I had two spare repeater bulbs so those are brand new now. I'll buy a couple of brake lights just to rule that out...It's just crazy. Hazard lights and pressing the brake makes a disco effect :))) Not sure if to laugh or cry
 

snapjim

Guest
Give the plugs to the light clusters a good clean with wd40 and leave to dry. Solves this problem most of the time. My old golf and the wife's 306 suffered the same thing and cured with a clean.
 

Juve

Active Member
Feb 9, 2014
23
0
Reading
Give the plugs to the light clusters a good clean with wd40 and leave to dry. Solves this problem most of the time. My old golf and the wife's 306 suffered the same thing and cured with a clean.

Cheers, I looked at them and they are all clean, no dirt, corrosion but I'll WD40 them as well.
You are referring to the inside of the cluster where the bulb touches the connectors, right?
 

snapjim

Guest
No where the wires plug into them, accessible from inside the boot, do the plug and the socket. Good luck.
 

Juve

Active Member
Feb 9, 2014
23
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Hey guys, sooo happy, finally sorted it out. Ended up by removing just about all the boot trim, clusters, whatever I could get to.

On the passenger side just above the wheel arch is a point for grounding wires. There are 3 cables that go there. One smaller brown one, then a plastic separator and then 2 larger black ones secured with a nut. Somehow the brown one loosened and was touching the other two. Removed the nut, set them straight and screwed the nut and all returned to normal.

Thank you all for the help provided.

Cheers
 

waynedunn1234

Active Member
Aug 23, 2013
56
0
Hey guys, sooo happy, finally sorted it out. Ended up by removing just about all the boot trim, clusters, whatever I could get to.

On the passenger side just above the wheel arch is a point for grounding wires. There are 3 cables that go there. One smaller brown one, then a plastic separator and then 2 larger black ones secured with a nut. Somehow the brown one loosened and was touching the other two. Removed the nut, set them straight and screwed the nut and all returned to normal.

Thank you all for the help provided.

Cheers

LOL thats a great result. its crazy that one small wire that could cause all the light problems.

write a guide for how you fixed it as no doubt someone else will have the same problem
 

Juve

Active Member
Feb 9, 2014
23
0
Reading
Unfortunatelly I didn't think to take pictures.

In order to get to the wiring you need to take a few pieces of trim off.

Best to start with the trim that covers the boot latch. Not the one on the boot door, the one on where it grabs. There are 2 nuts just at the back of the spare wheel. Unscrew those and then it is just clips into place. You need to use a bit of force but do not pull to hard as you can brake it.

Once that is out you need to move towards the passenger cluster side. There is a screw just next to the cluster. Take that out and the trip clips in place just like any other. Again a bit of force but be gentle at the same time.

The next one is the side trim where the boot light is. Don't forget to take the light out first. Just pry it loose with a screwdriver and unplug the it. There are 3 screws that hold that trim in. One is on the back of the rear seats. Just fold the seat down and you can easily unscrew it from the back door.

After you've taken this out you will see the loom behind it going in all directions. The issue I had was with the ground wires which are held in place with a nut. I had 3 cables tied there. Two larger black ones and a brown one. There is a plastic washer that stops the brown one from touching the 2 black ones so make sure they don't touch and are on opposite sides of the washer.

You should have the brown cable first, then the plastic washer then the 2 black cables and finally the nut. As the 2 black cables are quite rigid if they haven't been tightly screwed into place the washer can move and allow the brown cable to become a bit loose.

I've bent the black cables a bit, screwed them tightly in place and all the issues were resolved.

*** As a bonus to it I used to have an intermittent issue with the rear screen wiper. It only worked when it wanted to. Since I did this it works brilliantly so most likely that was linked as well.

The trim goes back the other way around just be careful not to brake any of it. It is not too fragile but it's plastic after all.

Also, looking around I believe there is a second grounding point on the driver's side but I didn't get to take the trim out on that side so can't be sure. I just had a glimpse at it when looking around.
 
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