12V Power outlet in Not Working Properly

[Ernie]

Hi Folks,

Need some help please. I have a 2003 2400SC. It has 2 12V sockets one on the dash and one in the cuddy. Neither of them seem to be working properly. I have just bought the boat. I checked the cables with a volt meter and all seems ok. The reading on the meter was 12.55 Volts. However, nothing works when plugged in. I changed the socket today to see if it was the socket itself which was faulty but the new one (which I was told by the owner of the boat spares shop was actually better than the original) didn't work either. When I plug my phone charger in the light on the part of the charger which is inserted into the socket lights up but it won't charge the phone itself. It is obviously getting some sort of power but not enough to actually power anything. Everything is in working order because I tried everything in my car socket and they work perfectly.

The boat currently has just one battery. The battery is one of the larger ones, is brand new and has a full charge. The engine is the MPi 5.7L 350MAG.

Can anyone help with this please?

Thanks,

[forbes210]

I had problem with one of my 12v sockets as well. Who ever was working on my boat before made some mess. It came out that connected wires to the socket were flipped. I burned few phone chargers before I figure it out

[Ernie]

Hi, if the wires were flipped on mine then would that not mean that there was zero power from the socket? As I said it lights up the charger part of my phone charger but that's all.... its frustrating as I can't use anything... phone charger, 12V TV, etc..

Thanks

[mmwjr]

I think what forbes is saying that 12V + and ground were backwards.

Using a voltmeter touch the positive lead to the center contact of the socket and the negative lead to the side metal contact. It should read +12V if so it's ok else if -12V the wires are backwards.

[stiches]

Does it say -12.55 volts on the meter? Negative 12.55

[stiches]

Oh you beat me to it Mike.

[Ernie]

Hi Mike, when I used the volt meter on the 2 wires going into the socket in the cuddy the meter read 12.55 not -12.55. So based on that you would expect it to work fine. However, it doesn't. I tried several different things in it, all obviously 12V items - phone charger, TV, 12V extension cable, etc. and nothing is getting any power. The light power light on all of the items are lighting up so they are getting some sort of power but seems that its not enough to power anything. For example, on the 12V power lead for the TV, the part that is inserted into the socket lights up. However, there is then a cable which runs to a square shaped box type thing then another cable leads from this and plugs into the TV. There is also a power indicator light on this black box but that's not lighting up and the TV isn't getting power... It's confusing....

Any thoughts?

Thanks,

[mmwjr]

Try measuring the socket voltage while one of the devices is plugged in to see if it still reads 12V. If not then you may have to trace back to where the power is good (fuse box) cleaning any connections which may be causing a voltage drop.
If the voltage is good I would use a plug that you can cut the wire on and stip the ends so you can measure for voltage when it is plugged in.

Let me know what you find from here.

[Ernie]

Thanks I will try that, Mike.

I'm no expert but I'm guessing that because the charger light is coming on when I plug it in then it's not an issue with a damaged fuse or breaker circuit? If that was the case then no power at all would be getting to the 2 wires that connect to the back of the socket?

Also, this may be a really stupid question but does the ignition need to be switched on for the 12V outlets to work? Or does one of the AUX switches on the dash board need to be on for the outlets to work? Just trying to rule out anything obvious....

Thanks

[mmwjr]

Originally Posted by Ernie

Thanks I will try that, Mike.

I'm no expert but I'm guessing that because the charger light is coming on when I plug it in then it's not an issue with a damaged fuse or breaker circuit? If that was the case then no power at all would be getting to the 2 wires that connect to the back of the socket?

Also, this may be a really stupid question but does the ignition need to be switched on for the 12V outlets to work? Or does one of the AUX switches on the dash board need to be on for the outlets to work? Just trying to rule out anything obvious....

Thanks

Not sure as I have seen it either way. However when you are plugging into to the socket and get the charger light to come on do you need to have any switch or the key on? No power no light.

I am just wondering if the boats sockets are not mating properly with what you are plugging in for some reason.

[Ernie]

Mike, I was thinking that myself about the sockets not mating properly but don't think that's the case. I fitted a brand new socket yesterday which I was told was better than original because there was much more metal inside the socket and should therefore give a better connection.... however, this didn't work either..

I'm going to go down tonight. How do I test the voltage with a meter with an appliance plugged into the socket? where do I touch with the earth and positive?

Cheers

[shrew]

I'd try using a volt meter and testing the voltage coming into the back of the lighter. Then I would take some junk 12v lighter adapter, cut the cable about 1 ft. back from the connector, split and strip the sides. then test Those connections to see if you're still getting 12v.

[mmwjr]

Originally Posted by shrew

I'd try using a volt meter and testing the voltage coming into the back of the lighter. Then I would take some junk 12v lighter adapter, cut the cable about 1 ft. back from the connector, split and strip the sides. then test Those connections to see if you're still getting 12v.

This is what I was attempting to say in my last post.

[Ernie]

Well, after all that I tried taking the socket fuse out to see if it looked ok.... it did. I put it back in and..... Bob's your uncle! problem solved! both sockets are now working perfect! must have been a bad connection with the fuse...

Thanks everyone for the advice!

Cheers

[mmwjr]

Isuspect the fuse had oxide on its contacts that acted as a resistor limiting current and causing a voltage drop when you plugged into the socket. Removing and reinstalling wiped off the oxide.

[shrew]

When I was doing a more compputer hardware related role many years ago, we had to common unseat and reseat cards in servers and pc's for the same reason.

[njones]

The light bulb in your charger will work no matter which way the current is flowing through it. Your device however, will not. It certainly does sound like the polarity is reversed to your outlets.

[mmwjr]

Originally Posted by njones

The light bulb in your charger will work no matter which way the current is flowing through it. Your device however, will not. It certainly does sound like the polarity is reversed to your outlets.

Actually most lights in portable devices are LEDs and they are polarity sensitive.

[Ernie]

That's a lesson learned folks... check the fuse!!