Technical How can I prevent water getting into lights?

[Cam3roon2k41999]

Hi, I have a 2006 fiat grande Punto.
On Wednesday we had quite heavy rainfall and I noticed that my rear Left brake light and taillight was not working , so I got new bulbs but still didn’t work. The next day I noticed someone before me had put an extra earth wire on the left tail light and the connector was a little rusty. After cleaning it the light now works but flickers on and off if I tap the Unit etc.. yesterday when I was driving both front headlights went out for about 5 seconds then came back on then about 15 mins later when I got out the car the number plate lights stayed on then went off after about 10 seconds. Today after a short journey I tried to start the car and the starter was grinding as if the battery was dead. After jumping the battery the voltage with the engine running was 13.98v and without the engine started it was 12.65v. I have checked the grounds for corrosion and all seem fine. It’s just random electrical glitches that seem to be happening BUT the fuse box seal under the bonnet seems bust so I’m thinking water might of entered that and/or the lights during the rain, could anyone confirm if water could be the issue or is it something more serious? Thanks

 

[spidermania]

How can I prevent water getting into lights?​

Run a bead of clear silicone around the seam of the light housing, provided there is a seam. If wires are running through a grommet perhaps change the grommet or seal that up as well with the silicone. The lights have to breath to let the heat build up out, so be careful with the silicone or they may melt. And halogen burns hotter then led. If they are incandescent type should be ok. I had to change my entire set out on my van earlier this year after moisture got into them, and what a job that was.

 

[Cam3roon2k41999]

Run a bead of clear silicone around the seam of the light housing, provided there is a seam. If wires are running through a grommet perhaps change the grommet or seal that up as well with the silicone. The light have to breath to let the heat build up out, so be careful with the silicone or they may melt. And halogen burns hotter then led. If they are incandescent type should be ok. I had to change my entire set out on my van earlier this year after moisture got into them, and what a job that was.

View attachment 453616

i don’t think the front headlights have any water in when I checked but I can’t seem to replicate any of the faults now haha. I think we are getting heavy rain again in a couple of days hopefully(never thought I’d say that lol) then I’ll be able to see if the issues come back. I kind of hope they do that way I know it’s water otherwise I don’t have a clue what it is. I checked the fuse box and doesn’t look like any water has entered but it’s not locking in place properly. Thanks

 

[spidermania]

I checked the fuse box and doesn’t look like any water has entered but it’s not locking in place properly.

Try to get it seated properly closed because if you get water in there kiss the car goodbye.

 

[Cam3roon2k41999]

Try to get it seated properly closed because if you get water in there kiss the car goodbye.

Oh will it destroy all the electrics? I thought it might just trip some stuff.

 

[spidermania]

I suppose it could go either way, but as that old saying goes, 'better safe than sorry'.

 

[Cam3roon2k41999]

I suppose it could go either way, but as that old saying goes, 'better safe than sorry'.

Definitely lol. I think the clips have snapped on the lid, would it be ok to use some plastic film on top of the fuses just as a temporary measure until I get a new one?

 

[spidermania]

Yes indeed ! It doesn't have to breath, cover it up.

 

[Cam3roon2k41999]

Yes indeed ! It doesn't have to breath, cover it up.

Thanks I’ll do that. Is it possible these faults could be a bad battery? The voltage when the car wouldn’t start was at 12.03v but today it was at 12.65v with the engine off. It does look like an old battery though

 

[spidermania]

I can't answer that but stay around because we have top people on this forum who can probably help explain it. What we want to do is protect your wiring harness, because if you have to eventually rewire the entire car it may cost more than the car is worth.

 

[AnthonyH]

No water will be getting in there, it'll be rusty or loose connections around the lights and their wiring. The Grande Puntos are renowned for this problem, it keeps coming back, so you'll get used to fixing it, and it's nothing serious, just annoying.

And buy a battery tester, or ask Halfords for a free battery check.

 

[Cam3roon2k41999]

No water will be getting in there, it'll be rusty or loose connections around the lights and their wiring. The Grande Puntos are renowned for this problem, it keeps coming back, so you'll get used to fixing it, and it's nothing serious, just annoying.

And buy a battery tester, or ask Halfords for a free battery check.

Thanks for the reply, I’m glad it’ll be nothing serious, I tested the battery voltage when I came back home earlier so I’ll probably test it again tomorrow to see if there’s a drop in voltage.

 

[AnthonyH]

The battery can show 12.5v and still be at for example 20% health. So you'd need a battery health check, not a voltage check. You can buy kit that does this.

 

[Cam3roon2k41999]

The battery can show 12.5v and still be at for example 20% health. So you'd need a battery health check, not a voltage check. You can buy kit that does this.

Sorry for the late reply, I didn’t know that. We had quite allot of rain again today so I’ll be going out sometime to check if there’s any faults. Will this tester be ok for the battery? Thanks

 

[AnthonyH]

Sorry for the late reply, I didn’t know that. We had quite allot of rain again today so I’ll be going out sometime to check if there’s any faults. Will this tester be ok for the battery? Thanks

It looks like that tells you whether the battery is in a state of partial or full charge but not the health of the battery. So on the surface it doesn't look any more useful than a voltage check.

I bought the one below, its a lot more expensive i'm afraid, but it'll give you some kind of idea what you're looking for. With this piece of kit you enter the cold cranking amps of your battery, for example 500 CCA, and then the kit does a cold crank test on the battery. If the kit returns your battery is capable of 250 CCA, then your battery is at 50% health and you might want to change it. You could go to Halfords and get a free battery health check.

https://www.amazon.co.uk/dp/B09CYHCQ7C

 

[Cam3roon2k41999]

It looks like that tells you whether the battery is in a state of partial or full charge but not the health of the battery. So on the surface it doesn't look any more useful than a voltage check.

I bought the one below, its a lot more expensive i'm afraid, but it'll give you some kind of idea what you're looking for. With this piece of kit you enter the cold cranking amps of your battery, for example 500 CCA, and then the kit does a cold crank test on the battery. If the kit returns your battery is capable of 250 CCA, then your battery is at 50% health and you might want to change it. You could go to Halfords and get a free battery health check.

https://www.amazon.co.uk/dp/B09CYHCQ7C

Ah right I see, £45 but 20% off voucher might add that to my tool box lol. I might go to Halfords first to see what they say. Thanks

 

[Cam3roon2k41999]

It looks like that tells you whether the battery is in a state of partial or full charge but not the health of the battery. So on the surface it doesn't look any more useful than a voltage check.

I bought the one below, its a lot more expensive i'm afraid, but it'll give you some kind of idea what you're looking for. With this piece of kit you enter the cold cranking amps of your battery, for example 500 CCA, and then the kit does a cold crank test on the battery. If the kit returns your battery is capable of 250 CCA, then your battery is at 50% health and you might want to change it. You could go to Halfords and get a free battery health check.

https://www.amazon.co.uk/dp/B09CYHCQ7C

Thanks, I’ve just been to Halfords for a check, came back 96% health. I noticed today that the radio lights behind the buttons were illuminating again without the ignition on. It’s been doing that since I’ve had the car but none of the lights work behind the heater controls could that possibly affect the radio lights? It’s the only thing I can think of

 

[AnthonyH]

Thanks, I’ve just been to Halfords for a check, came back 96% health. I noticed today that the radio lights behind the buttons were illuminating again without the ignition on. It’s been doing that since I’ve had the car but none of the lights work behind the heater controls could that possibly affect the radio lights? It’s the only thing I can think of

I don't think those things are connected, this is all part of the "Punto experience" lol

 

[Cam3roon2k41999]

I don't think those things are connected, this is all part of the "Punto experience" lol

I can’t really complain (yet) my mk5 golf had way more issues than my Punto electrical issues popping up everywhere. I’m not sure how much of a drain they are causing but if I leave it for a couple of days it starts straight up again , it’s just annoying lol

 

[AnthonyH]

I can’t really complain (yet) my mk5 golf had way more issues than my Punto electrical issues popping up everywhere. I’m not sure how much of a drain they are causing but if I leave it for a couple of days it starts straight up again , it’s just annoying lol

If my 2 Puntos were people they'd be at the gp surgery or hospital every week lol. Its a never ending train, of flashing bulb warning lights, boots that don't open, key fobs that stop working, etc. oh well lol They take turns in going bad so at least I always have one car on the road!