Power ports

Steve Hunt · 11-12-2022, 01:07 PM

I noticed in the owners manual of my 2008 E350 it says to not use the cigarette lighter port as a accessory power port? Curious what the reasoning is ? I have actually used it for several years with a adapter that gives me 2 USB outlets for phone charging...then i stumbled across this statement in the manual the other day. Of course it doesn't tell you why.

Twoxentrix · 11-12-2022, 05:05 PM

Interesting, I also run two phone cables off mine (occasionally 3) - can't imagine this would be an issue, but now I'm interested in what response you get Steve.

AndrewInSeattle · 11-12-2022, 08:20 PM

Assuming you're talking about the dashboard's lighter, isn't that just a precaution to avoid draining your starting battery? Not a big deal for charging phones, but if you plugged in a 12V coffee maker or similar while boondocking, and didn't think deeply about your power consumption, you could be in a bit of a pickle.

BrianW · 11-13-2022, 06:38 AM

Probably also has to do with the gauge of wiring that’s run to the 12v socket. Most cash sockets I’ve seen have pretty small-gauge wiring that wouldn’t like a high-draw 12v accessory.

86Scotty · 11-13-2022, 06:47 AM

I'm sure they mean while parked/camping. It would've been pretty easy though to say that, and to piggyback what's in the van's owner's manual about what those outlets can handle/fuse size etc.

Scalf77 · 11-13-2022, 07:53 AM

The best that I could find, all the power ports have 20 amp circuits. The cigarette lighter port circuit is shared with the data link connector, so that may be the difference. I would not worry about the standard usb chargers. Now some of these 100 watt USB C Fast charge options I would, but I also have concerns on their cooling abilities also.

-greg

ShuttlePilot · 11-13-2022, 09:11 AM

Quote:

Originally Posted by Scalf77

The best that I could find, all the power ports have 20 amp circuits. The cigarette lighter port circuit is shared with the data link connector, so that may be the difference. I would not worry about the standard usb chargers. Now some of these 100 watt USB C Fast charge options I would, but I also have concerns on their cooling abilities also.

-greg

Years ago I ran a dedicated large gauge wire, ground and fuse to the cigarette lighter port from the house battery buss bars. Mainly to have another house powered 12v port available than any deficiency in the factory wiring. I do feel more confident plugging in higher current loads/chargers with the larger wires that are not part of the van harness. Have to look but I think I'm protecting it with a 30A fuse now. I left the second 12v port powered by the starter batteries so I have options. I find it optimistic that the circuit would be labeled 20 amps as the wire to the lighter socket it pretty small gauge. I have seen many 12v ports labeled 10A max but that might be a continuous rating. Maybe the lighter heating element is higher than 10A but for a known duration or duty cycle. Anyway, not many vehicles with cigarette lighters to talk about any more.

- Eric

deserteagle56 · 11-13-2022, 10:04 AM

When I tried using the cigarette lighter port to power my portable compressor (airing up the tires) it would blow the fuse to the port. Had to use alligator clips directly to the battery.

Steve Hunt · 11-13-2022, 11:14 AM

Thanks all, based on the input I'm going to keep using the cigarette power port for my GPS and the other port for the dual USB adapter. I always assumed there were two dash OEM power ports and never thought about one being a cigarette lighter port till stumbling on the comment in the manual. It sure does seem that the better way to address the ports would be to simply say what each is limited to amp-wise and then a reminder that they are connected to the start battery....or make them "switched" but I'm glad they are not switched. It's nice to fiddle with the GPS at stops without involving the ignition key.

86Scotty · 11-14-2022, 07:21 AM

Quote:

Originally Posted by Scalf77

The best that I could find, all the power ports have 20 amp circuits. The cigarette lighter port circuit is shared with the data link connector, so that may be the difference. I would not worry about the standard usb chargers. Now some of these 100 watt USB C Fast charge options I would, but I also have concerns on their cooling abilities also.

-greg

Agreed, the problem with these newer higher wattage chargers that we demand for our thirsty electronics is that they are so cheaply produced. They are so common that you can pay $5 for one on Amazon and you get exactly what you pay for. It's also very hard to tell the quality control of the 'better' brands these days, hard to distinguish knock-offs of the better brands and what exactly a better brand is if you haven't been buying these for long.

I trust a few names and cheaper/newer options are always suspect. Better, more long standing brands are:

Anker
Griffin
Belkin
Scosche

This is a broader statement about things we plug in to cigarette lighters/charger ports but I've never had an OEM cable or charger for any electronic fail while about every other cord/charger I've had eventually does.