Hey - new member and first post. Great forum with loads of helpful guides and posts. Looking forward to learning a lot about my Grande Punto.

I couldn't find anything here on replacing the loom that connects to the rear lights, so my question is around that for the 1.3 multijet diesel.

Water has got behind the light unit and corroded the spades on the light unit and also the connectors on the, well, connector at the end of the light loom. The brake lights flicker when indicating and I believe this is down to a bad connectivity/no earth. I also get a warning on my dash when indicating.

I've cleaned up the spades. I also bought a new lights unit with bulb holder but got the same issue, so I'm sure the problem is with the rust (and blue coating) on the connectors at the end of the light loom.

I wanted to try and manually clean the connector but didn't want to touch the connector until I was sure about current running through (I'm thinking the sensor that allows the dash to show when there's a blown bulb etc.) or whether I have to disconnect the battery or anything else I need to consider.

I am very new to doing anything to cars other than driving them and filling them up with fuel, so please excuse the basic question.

Am I safe to clean them up, say, with a flat head s/driver just to get a good connection? Without removing the connector? Or disconnecting the battery? (If the battery needs to be disconnected, which order do I need to remove the connectors in?)

My other option is to buy a new loom, but I'd need to get someone to fit that and would rather avoid that if possible.

Any advice, help or suggestions would be very helpful.

Thanks!

It's best to disconnect the battery. Although there SHOULDN'T be any current flowing when the lights are off, it's good practice and doesn't take long. You only need to drop the negative terminal off.

As for cleaning the contacts, You'll be fine doing what you suggest but once the plating has come off the terminals, they will corrode again. Best bet is to smear Vaseline or waterproof grease on them once you've cleaned them, but you might still find it's a regular job.

Also check the earth stud behind the left hand rear wheelarch carpet in the boot. If you pull that carpet away, you'll see the earth wires and the stud welded to the body. If in doubt, undo the terminals and give it a good wire brushing, then re-assemble.

get some proper contact cleaner

http://uk.rs-online.com/web/p/contact-cleaners/3883814/

http://www.3mdirect.co.uk/scotch-1625-electrical-contact-cleaner-400-ml.html

Thanks for the responses guys. VERY helpful. I will give this a go at the weekend when I can get some daylight hours.

Great shout about the contacts re-corroding, I need to do something about that. Would vaseline prevent the contact from connecting at all?

Re the contact cleaner; I did actually get some online last night, so I can do this properly, but again a great suggestion and great reassurance that I'm thinking along the right lines - which a n00b really needs!

I'll also get onto cleaning up the earths under the boot carpet, too. I wouldn't have considered that at all!

Thanks guys! I'll keep you posted and will posted back with any further questions as needed.

Hey all,

I did promise an update on this and I never got around to it, so I thought I'd update here and try to be as helpful as everyone else on this forum who helped me out

The issue was corrosion on the spade connectors (the two contacts on the connector that's connected to the car where the spades slide into). There was rust and various different coloured corrosion.

I did as suggested and bought some contact cleaner, vaseline and some wire brushes. I scraped off any rust where I could, although space was tight. I ended up scratching a lot of it off with a flathead screwdriver to get it ultra clean, and used a soft brush to get rid of any remaining dust and used contact cleaner. I cleaned up the spades in a similar way.

I coated the whole thing in vaseline, and also sealed the rubber seal on the light unit that keeps the water out.

After 3 attempts at this, it finally worked and held without re-corroding enough to cause any issue.

The only problem I noticed is that if I take it to a hand wash that uses jetwashers then water gets back in, the lamp lenses steam up and the rust reappears, but if I don't then the issue seems to stay away.

I hope that proves helpful to anyone else the may come across this issue and find this post.

Thanks again for everyone's help.