Too much voltage from bedroom 12v cigarette lighter port??

If he had the wrong polarity, there would be a negative sign on his digital multimeter. I guess that could be a reason that things are cooking.

Is the polarity backward? That would explain smoking things.
Unless there is a second power supply, it is near impossible to have a higher voltage at this socket then the rest.

I am not using utility power. only battery power with my generator off. brand new batteries. I have the IOTA Engineering DLS-30. Again, all other 12v outlets work fine.

Try unplugging from utility power and see if the spike goes away.
s/b same as battery terminal voltage at that point.

Thanks for the auto-range idea. that could be the cause of the short overload reading in the beginning. My FLIR meter has the ability to set the range static which I will try. Thanks Ramen, I will plan to disconnect everything and tone the line to see where it's running. The only explanation for burning up any 12v device I plug into it would be too much voltage/amperage considering I have tried two different 12v outlets (brand new). I will re-wire and call it a day. The toner should help with finding the line. Thanks again for everyone's input.

Unplug all other devices, voltage test from that outlet. Next step I would do is to disconnect battery/power and see what is behind that outlet and trace the wire back. I would install fuses if they don't already have them.

Autorange is easy to check by using same sequence testing on the battery direct.
Still does not explain stuff burning up.

My first thought was malfunctioning converter and no battery or battery disconnected.

versicom wrote:
what I mean by smoking is simply it burns up and 12v item I plug into the outlet.
Please give an example of what burned up...?

I am a computer engineer and quite capable with a multimeter. It should not be producing an overload when connected. It is clear to me that the outlet is getting to much voltage. I plan to rewire the socket which will not be an easy job as I do not know where the wires run. The owners manual came with no wiring schematics.

I tried to explain it to you.
Think this through, don't you find it strange that you only see this "spike" when you first connect the meter..? Ever wonder why there are no continuous spikes/high voltage readings...? Like I said above, its the auto ranging feature on your meter, momentarily showing overload while finding the correct range.

what I mean by smoking is simply it burns up and 12v item I plug into the outlet. I am a computer engineer and quite capable with a multimeter. It should not be producing an overload when connected. It is clear to me that the outlet is getting to much voltage. I plan to rewire the socket which will not be an easy job as I do not know where the wires run. The owners manual came with no wiring schematics.

versicom wrote:
Upon connecting the multimeter, I get a 20v "overload" spike and then 1 second later drops to 12.8v.

Common on many auto ranging multimeters to go to a overload reading momentarily while switching to the correct range. And it is diffidently not a spike, its the meter.
It means nothing and is normal. Has nothing to do with your dc voltage problem, if you even have one...

Explain in detail what you mean by...
"smoking whatever I plug into it"...


jmo