No power at helm cigarette lighter plug

[sb in gp]

Anybody have any tips on diagnosing / repairing the helm cigarette lighter plug? I'd like to use it to power my portable GPS and it has been out of commission since I bought the boat last fall.

Cabin lighter plug works fine.

Any help would be appreciated.

Scott

 

[Quint4]

checked the fuse on the + line that feeds the plug ?.....or maybe you'll get lucky and find a loose connection....good luck.

 

[sb in gp]

checked the fuse on the + line that feeds the plug ?.....or maybe you'll get lucky and find a loose connection....good luck.

Thanks Jim. I will check that as soon as I get the boat from storage. I assume I have to take the dash apart to get to that wiring?

While I'm in there is there an aux 12V connection under the dash that I could tap into for the GPS? Any recommendations for passing the wire through?

Scott

 

[Quint4]

I'm not familiar with your dash set-up.....funny you asked about tapping in for your gps...I tapped in to the 12v outlet wiring for my gps....worked great....my gps is a small one and draws very little amps....Dave.

 

[Petep]

Go up to Radio Shack and buy an inexpensive meter/tester. They will give you a quick lesson on how to use it and then you can find out where in the circuit the problem lies. It's a good thing to have in your tool box. Good luck.

 

[Wotty]

checked the fuse on the + line that feeds the plug ?.....or maybe you'll get lucky and find a loose connection....good luck.

Thanks Jim. I will check that as soon as I get the boat from storage. I assume I have to take the dash apart to get to that wiring? =snip=

Isn't there an access panel from the heads to the back of the dash ?? Fuse box may be there :smt001

 

[Dave M.]

Go up to Radio Shack and buy an inexpensive meter/tester. They will give you a quick lesson on how to use it and then you can find out where in the circuit the problem lies. It's a good thing to have in your tool box. Good luck.

I recommend that you not do that. If you are going to have a meter, get one you can trust, and that will give you the accuracy you need to determine electrical things like battery state of charge. Get a good Fluke meter or equivalent. It is late, maybe I will write more about this tomorrow.

I am biased. In my working life I almost sent a guy 90 miles one way on overtime to figure out why an operator found our communications battery voltage to be bad. After a bit of digging to understand how he could get such readings when I had no alarms, I asked what he was measuring with. It was a Radio Shack meter, and was just plain wrong. It is meant for the home hobbyist to use in situations that are relatively insignificant. OK to use it there.

OK, I will write a few words to define what you should have. A meter should be able to tell the difference between 80 and 85% state of charge on your battery. So look up what those voltages are, and make sure your meter can easily tell which your battery is when you read it, when the accuracy of the meter is right at the limit of its accuracy on the DC range you would use.

This thread belongs in the electrical section.

 

[sb in gp]

OK, I will write a few words to define what you should have. A meter should be able to tell the difference between 80 and 85% state of charge on your battery. So look up what those voltages are, and make sure your meter can easily tell which your battery is when you read it, when the accuracy of the meter is right at the limit of its accuracy on the DC range you would use.

Dave, can you recommend a specific product?

 

[Dave M.]

I did some looking at Fluke meters, and battery state of charge vs voltage on the net. For state of charge vs voltage, I see one site lists 75% charged as 12.45 V, and 100% as 12.65 V. So the change in voltage of 0.2 volts, 200mV, represents 25% state of charge. This is 4 mV per percent state of charge. Many meters on a scale that will read 12 volts have a maximum resolution of 10 mV, +- 1 count.

So 10mV resolution is 2.5% state of charge, plus a count error of 2.5%.

This is what the Fluke model 83V does. It is good enough, I think. But for a little more money you can get the model 87V that has a button that gives you 10 times more accuracy.

This considers resolution only. Then you have to add in the accuracy number. The model 83 has 0.1% accuracy, the model 87 is 0.05%. Both are good enough.

Either of these is a good choice. They are not cheap, but they are meant for full time commercial use, and I would expect them to last a lifetime. You might often find one of these in an electricians toolbag, along with his wrenches and screwdrivers. When he takes it out of the bag, puts in on the work table, it gets knocked off onto the concrete floor, he expects to pick it up and use it and have it meet spec.

What I have for home use is somewhat less spendy, it is a Wavetek DM27XT. It is a 2000 count DMM, not autoranging, but otherwise similar to the above. It does not have the soft yellow rubber outer shell that the Fluke has to protect it when dropped. It also has lower accuracy spec at 0.5%, which is barely good enough.

I see there are several Wavetek models for sale on eBay. I think if you get one that has an accuracy of 0.25%, and is 2000 count, then that would be good. I personally would not buy one off eBay unless I had a way to verify its accuracy. But I am sure you can get Wavetek models elsewhere.

I recommend you go by the count number, not the 'number of digits', such as 3 1/2, 3 3/4, 4 1/2 etc. A 2000 count unit will display up to the number 2000, with the decimal point set by the range. When the count goes over 2000, then you have to go up to the next range. So with a 2000 count unit, you could display battery voltage as 12.45 volts. The digits are less than 2000. With a 6000 count unit, you still have the same display, 12.45, though the unit may have a better accuracy number. You don't get more resolution when measuring a 12 volt battery until you get up to a 20000 count unit. Now you can display 12.456. Only the Fluke 87 can do this of the ones I have mentioned.

Basically, I would trust the Fluke, the Wavetek, and also meters by Extech.

 

[sb in gp]

Finally got around to dealing with this issue.

This problem turned out to be a poorly spliced wire from prior owner. They tried to tap into the hot wire to the lighter by using an aluminum crimp connector which did not hold. I respliced and soldered them together, covered the connection with a heat-shrink rubber tubing. Good to go!

Thanks.