Adding 12V Outlets

I want to add a 12V DC outlet to a 2005 Nissan Frontier. I tried a splitter, but that created some serious power issues re a GPS that was plugged in, eventually ruining the GPS.

Radioshack sells an auxiliary outlet, but I’m not sure if a direct connect to the battery or alternator is the way to go. Any suggestions?

I installed an extra 12V “cig lighter” socket under the dash on my car to semi-permanently install a gps. I just tied into a 12V wire off the ignition switch so the socket would be switched. I didn’t want to cut up the power cord that came with the gps, so I used the socket instead of hard wiring it.

I’m not sure what sort of “power issues” you had with the splitter, but you could just wire the extra outlet from the back of the current one. That’s what I did when I added a standard 12V socket to my BMW motorcycle. The BMW bikes use a “non-standard” outlet and I wanted to be able to use a 12V air pump and cell phone charger. No trouble with that.

If you really want to wire all the way to the source, I’d go to the battery, not the alternator. Use 2 heavy (14 or 12 ga) wires, both positive and ground all the way if you are worried about “clean” power, though I’d probably just find a good circuit at the fuse box if I were doing it.

I don’t know how you could ruin your GPS unless maybe you got the polarity reversed. Anyway, a direct connection to the battery, properly fused, is no different from tapping into an existing wire that is always hot. Maybe you would prefer one that is ignition-switched. Shrug. Get your auxiliary outlet and connect it to an existing wire such as the one that currently powers your lighter. There ought not be any unusual issues.

There is no way you could ruin an appliance plugged into an auxiliary outlet or a splitter. What’s the worse that can happen? you get less than the 12 volts needed.
Any thing well designed should either work with lower voltage or should shut down, not burn up.

If you direct connect to the battery (not the alternator) you really must have a fuse somewhere in the line, or you run the risk of a short, with burning insulation, toxic fumes and all the rest.

Actually, as most electronics gurus know, underpowering electronics is more deadly than overpowering them (up to a point). Most likely the GPS got toasted by reverse polarity but seriously underpowering any computerized electronics for extended periods is a recipe for disaster.

JMHO, but anything that draws more current than a basic radio head should not be routed through any of the vehicle’s wiring.
It should be routed directly from the battery or a distribution terminal and through a relay.

Relays are cheap, easy to wire in, and can possibly avert any future problems with overloaded wiring; or the usual, overloaded wire connectors.