Offside brake light flickers when indicators flash

Gingerposer · Unread post by **Gingerposer** » 11 Feb 2010, 19:48

Well, after changing all the bulbs at the front of my car (and being grateful for having relatively small hands) I decided to check the rears. Noticed that the offside brake light flickers in time with the indicator on that side. No flicker on the nearside. Had the unit out of the car, checked the bulbs, the contacts under where the bulbs fit, and the wiring plug. All seems in good condition.

Where do I go from here to try to establish what is causing this, before it becomes worse?

Car is a 2000 registered 1.8 16v Forte hatch.

Cheers
Ainslie

Homer · Unread post by **Homer** » 12 Feb 2010, 00:13

This kind of thing is generally a poor earth so I'd check that first.

rmunns · Unread post by **rmunns** » 12 Feb 2010, 08:06

Yes, poor earth. Look for earthing lead near to the fitting.

Gingerposer · Unread post by **Gingerposer** » 12 Feb 2010, 08:19

Ok will do that. Does anyone happen to know where I will find the earthing point, before I go removing boot carpet, wheel arch liners etc?

Cheers

Ainslie

Unread post by **CitroJim** » 12 Feb 2010, 08:30

The earth point, designated MC71, is just below the RH lamp cluster. It should be accessible from within the boot, under the carpet.

This earth serves all lights at the rear.

This fault can also crop up if there is an earth fault within the lamp cluster itself. Bad body contact on the bulbs itself can cause it. Check all bulbs are making good contact with the earth bar and that their metal bodies are clean.

Gingerposer · Unread post by **Gingerposer** » 12 Feb 2010, 11:10

Well. I have had a bash but now it's blinding sunshine outside so I can't tell if it has worked or not!

Was quite straightforward really, once Citrojim had told me where to find the earthing point and saving me wasting time hunting.

I took a couple of pics with mobile as I worked, so I 'll upload these here (if I can figure out how), who knows, it may be useful to someone else in future.

First I removed the trim panel at the rear of the boot - removing four circular plastic covers exposes four T15 screws.

Then removed the trim panel in the offside corner, again removing one T15 screw to do so.

Finally carefully pulled back the boot carpet in that corner exposed the earthing point. It's not necessary to unscrew the butterfly nut holding in the light cluster but since I was removing this for a clean anyway I did so.

10mm spanner to undo the earthing bolt, then gave the contacts a quick rub with fine sandpaper, and a spray with electrical switch cleaner. Same with the back of the earthing bolt to ensure a good contact.

Finally, removed the light cluster, removed the bulb holder from it, removed both bulbs, gently sanded all contacts: the four in the wiring lug socket and those which supply power to the bulbs. Also rubbed the contact points of the bulbs while they were out.

Took about 15 mins all in. I'll check the lights tonight once it's dark and report back.

Cheers

Ainslie

Clogzz · Unread post by **Clogzz** » 12 Feb 2010, 13:36

Had that, caused by water in the cluster.
The seal let water in, corroding the earth connector.

http://www.frenchcarforum.co.uk/forum/v ... hp?t=21367

Gingerposer · Unread post by **Gingerposer** » 12 Feb 2010, 20:10

No More Flicker!