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Cigarette lighter intermittent when charging electronics

2008 civic.

I’ve got a 2-USB to cigarette-lighter adapter that I use to charge my own phone and that of my passenger.

Lately the power has been cutting out. Wiggling/twisting the adapter can reconnect it, but often only very briefly. I find I have to wiggle it a good deal until it finally establishes a good connection and I’m good to drive for a while. Back at it again, however, in a day or two.

So it’s obviously not the fuse, since it works most of the time. And I see no visible corrosion to prevent a good connection.

Any thoughts on what to look at next? Do these ports just work their way loose in the back after a few years? Or might it be bent contacts or something?

If this is the only device that has the problem it may be that the springs that push its contacts out have weakened. Spray contact cleaner into the socket, brush it with an old toothbrush. An extension: a male plug connected to a female socket, may make a better connection. I used to live out of my pickup and plugged in a lot of things: radios, computers, lights, phone charger… I built my own adaptors from scavenged parts. There wasn’t anything I couldn’t fix if I could take it apart. I’m no motorhead: I’m not bragging, just telling you how simple it can be. You probably have to take it apart yourself.

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Sounds about right.

Normally with any diagnosis of the problem is to use another cig lighter adapter and cord.

Many times it is the poor quality cig lighter adapter made off shore.
Still possible the cig socket has loose connection but 95% it’s the adapter

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Those adapters are cheap and generally throw-away. You might take a small screwdriver and bend the contacts on the side out a bit and see if that works. Also adding a wrap or 3 of electrical tape above the contacts so the adapter fits in the socket snugly can help, too. Or chuck it and get another one.

Another vote for replacing the adaptor, not a major expense.

There is a difference between a power point and a cig lighter. I have one of each, and on the cig lighter, intermittent success, on the power point 100 success. If it is indeed a cig lighter, you could replace it with a power point, or see if there is a power point is available for use.

I thought they (power point vs cig lighter socket) were the same ???

No they are not, at least in my car. @BillRussell. Power point won’t work the cig lighter, and cig lighter has issues with phone and gps power supplies.

This sounds like the same problem I have with flashlight batteries not making a good connection inside the flashlight. they work ok for a while, then become intermittent. If I shake the flashlight, bingo, but it soon fails again. The batteries are still ok b/c if I take them out, reposition, and put them back in again the flashlight works again. So the problem is at the connection between the batteries and the flashlight spring/clips. When I look at those I see no corrosion or dirt or anything unusual. I think what happens is the current flow when the flashlight is on is causing some kind of electrochemical plating of those metal part, and an oxide is forming which has a high resistance. If you’ve ever tried to solder to those kinds of connections, you know it doesn’t take solder well, so the metal must be some kind of alloy. Probably an aluminum alloy, and the resistive oxide that forms is aluminum oxide, which looks similar to aluminum metal and is why you can’t clearly see it.

Here’s my take: You won’t be able to fix this problem long-term. If you buy another one of those gadgets, the same thing will happen. If I had that problem I’d find the wires going to the cigarette lighter under the dash and splice into them with a connector pigtail, and put the other sex of that connector onto your usb charger wires. Cut off the adapter in other words, and replace with the matching connector. Then you’d always have a good connection available for charging your phone using the cig lighter’s fused circuit. Some caution is needed in choosing the style of connectors b/c the one connected under the dash will be hot at all times. You don’t want any exposed metal on that side of the connector.

I wish flashlight batteries came with little connectors rather than the point contact method they now use, so I wouldn’t have to battle this problem with my flashlights. I don’t think I’ve ever had a flashlight that didn’t develop this problem eventually. Any battery manufactures listening?

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In response to George, the contact parts are perhaps plated, which would explain why they don’t take solder well. And the problem that limbodog has with his lighter insert might be solved in the same way that a soldering issue would be: remove the plating from the steel or brass contact points. A bit of filing, and bending springy contact wires or tabs so that they make surer contact with the insides of the lighter port, could be the answer.

If that fails, I’d go for a replacement lighter-port adapter.

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