New Guy With Aygo Rear Lights Problem

[Planemo]

Hello people,

Great site here! I am hoping that someone could help me. Today I bought myself a 56 plate Aygo Sport manual with 48k on the clock. Neither of the rear sidelights or brake lights work, although the front sidelights are working, as is the high level brake light. All the fuses have been checked both under the bonnet and binnacle cover and the rear stop/tail bulbs are OK. I am slowly working my way through all the helpful threads on the forum but a search shows nothing specific to my problem. Has anyone got any ideas?

Any help would be greatly appreciated!

[Planemo]

Sorry, I should add that the numberplate lights are not working either, althouth the rear fog and turn signals are. Irritatingly, I went all over the car prior to purchase but stupidly omitted to do a light check. Schoolboy error!

[Raistlin]

Possible issues:

Loss of Power or Ground.

Possible Open at Switch to That Circuit.

Try Second Bulb.

If Neither Light Works

First Check Fuses

Then Check Brake Light Switch.

[Planemo]

Hi Raistlin,

Both rear clusters have the same problem. The brake lights and side lights do not work.

I don't think it is an earth issue because the clusters share their earths with the other bulbs such as rear fog, indicators and reversing light, which all work fine.

It's not the brake light switch because the high level works.

I have tried new bulbs - makes no difference. I guess it would also be unusal for both to go at the same time too.

I have spent most of today doing wiring checks, ripping up the seals/carpet and tracing the loom back from the clusters up to the steering column. I can't find any problems anywhere.

All the fuses are fine, and have been checked with a multimeter.

The only area I haven't checked, as I can't get to it easily is the area behind the dash.

This has to be something simple, but I am starting to get a headache over this as locating it is proving to be a nightmare.

I really can't afford to put it into Toyota for hours of diagnostics :(

[Planemo]

All other electrics on the car are working as they should. The dash lights including the radio and heater lighting also work. I have a haynes manual on order so i can try and find out where the outputs for the rear stop/tail lights come from but its gonna be a few days delivery and i really need to sort this now as i am without a car :(

[Uncle Bob]

First off welcome to the club :)

Sounds like a tricky problem, if you have checked the wiring loom, maybe It could be a fault or power feed to the column light switch.

Have you pulled the brake light switch plug off and put a wire across both connections to bypass the switch ?

[Uncle Bob]

Arrr..... Looking in the Haynes manual wiring diagram, back light, stop light, and no plate lights share the same earthing point, you could try adding an earth wire from the body to the light cluster earth, just to see if it works.

No mention in the manual were the earthing point is, try take the rear boot side carpets out and have a root about.

[eygo]

the aygo's have a lot of issues with leaking rear lights have you checked to make sure the contacts in the light plugs haven't corroded

[Planemo]

Hello guys,

Thanks for all your help, it really is appreciated. I have now solved the mystery and unfortunately, despite your best efforts, I don't think any of you could have diagnosed this one..

I'll start off by going back a bit - When I bought the car I saw some minor damage around the drivers side door lock. I noted it out to the seller and he said that as far as he knew, the car had never been stolen and the damage was there when he bought it. He had only had the car 8 months, only occasionally drove it to work during the day and had never had an issue with locking the car with the original key and had never put an MOT on it. I knew the door damage was a minor fix and haggled accordingly before thinking nothing more of it.

Whilst sticking my nose into every centimeter of the the wiring run from the rear clusters to the front of the car, I peered up underneath the dash and not surprisingly found various heaps of bundled wiring. In an attempt to solve my problem, I was on the move to pulling out the dash anyway and getting to everything between the switch stalks and rear looms to try and trace the problem but whilst looking up, I saw, tucked away in a corner, that a blue wire and a brown wire had been cut. They were very discrete, I only saw them out of chance. I was gobsmacked. WTF? I then looked closer and saw that a thick black wire nearby had also been cut, but the cut hadn't quite made it through all the wire and a couple of strands were hanging on, as well as a small part of the insulation. I couldn't see the wires properly, they were right up above the pedals and I certainly couldn't repair them with the access I had.

Out came the dash so I could see what the hell was going on. I separated the cut brown and blue wires. By this time I knew that the rear side lights and brakes lights corresponded to these colours so I immediately thought it was fishy but at the time I couldn't work out why and to be honest just wanted to repair them, thinking that doing so would be too good to be true. I repaired the two wires, along with the thick black one for good measure. Knowing that these three had been cut I had a good look around for any other evidence of skullduggery but couldn't find anything. I powered up, checked the circuits and !Removed! hell all the rear sidelights, brakelights and numberplate lights worked!

Having thought about it, I can only assume that the car was indeed an 'attempted theft', given the lock damage. Why the thieves had cut the rear light circuits I have no idea. I can understand the black, I presume it carries some sort of important current (not sure what - I never checked) but why knock out the rear lights? In any event, the access to them was really difficult and no other wires were cut, so I can only assume that they had an idea what they were doing. The car has never been reported stolen and I guess that the seller had driven around without any sidelights or brake lights (except the high level) since he had bought it. It had only covered 2000 miles in the time he had it so it could be possible.

Anyway, all is now sorted, and it just goes to show, buying a used car is just like a box of chocolates!

Cheers all.

[Uncle Bob]

I did think many rear crash damage and the earth had not been connected but I never would have expected your explanation of events....anyway glad it all sorted, we can put you down as Aygo wiring expert now :)

[Raistlin]

Well mystery solved and you're right we would never have guessed that issue.

Glad its all working ;)

[eygo]

hi planemo

the rear lights probably had the wires cut so the car would be harder to spot and follow at night.

[Planemo]

Thats what I thought too - but would it not be simpler to just not turn the lights on?! Unless they wanted to knock out the brake lights. But then the high level worked - maybe they just didn't get as far as finding the wire for that too...

Oh, I forgot to mention - the front sidelight bulbs were missing when I bought it too - although the main/dip bulbs were present (and worked). It's all very odd!

[Uncle Bob]

Can't think what crime you would do in a car that only wanted headlights working...maybe get away car but an Aygo is not wat you call brisk, although it would be nippy around the streets and would fit down alleyways.

[Raistlin]

How many avant garde surrealists does it take to replace an Aygo sidelight bulb?

Tomato

[stevecrvn]

Just a thought has the car had been converted by a previous owner to tow behind a motorhome . I belive some of these convertions have electrical conections to the towed vehicle but I am not sure where and How. Maybe they havr been removed and not conneted back up ?

[Planemo]

No signs of being converted, and if this was the case, there would be a lot easier ways of doing it than getting to the wires that were cut! The minor damage to the door lock is sus anyway I guess.

[eygo]

Just a thought has the car had been converted by a previous owner to tow behind a motorhome . I belive some of these convertions have electrical conections to the towed vehicle but I am not sure where and How. Maybe they havr been removed and not conneted back up

probably like if you have to call out breakdown / recovery company they can put a trailer board on the rear of the towed vehicle and connect to their trailer socket on the back of the van