Assistance in Installing Rocker(?) Switch for 2012 Prius

I added a USB "outlet".. (same size/profile) under the shifter shelf down by the accessories tray using a Dremel tool to cut open the hole...

 

Get an automotive test light ($3 at Harbor Freight)... The black wire attaches to ground, so you bolt it to the metal frame of the car behind the dash... Then connect the test light to the ground and start poking around with the probe till it lights up and then splice into that wire.

There's lots of options for which wire to choose... You could choose a wire that's still live even when car is off, much like your dome light... Or if you prefer you can tap into a wire that is only live when car is turned on, your choice...

Usually it's easiest to tap into the wire that powers the cigarette lighter... You can tap into lots of different wires, but some of those wires might be unhappy with an increased electric load and throw warning lights or cause dimming/lack of performance of whatever circuit you tap into.

Then once you have it connected it plugs into the spare plug section near your dashlight dimmer. It's a super easy install... Alternatively you could take it to a car stereo installation place and pay them lots of money to do it for you. It'll take them about 10 minutes.

 

I trust you're not really asking so much how to physically install the thing there (if it's the right size, it should pop right in, after popping the switch blank out), but more how to complete the wiring. As PriusCamper suggested, the ground side can go to any nearby grounded metal bolt. Finding where to attach the other wire can be done by trial and error with a test light, or by looking up likely circuits in the wiring diagram (more info), such as those to the existing power outlets. The diagram will show how they are routed behind the dash and, often, junction connectors that they pass through, which sometimes make good places to pick them up.

You can go to an aftermarket sound shop and they'll be done in ten minutes, because they'll have stuck a T tap across the middle of some unlucky wire and mashed it down cockeyed with slip-joint pliers and called it good.

 

In High School in late 1980's I had a job doing car stereo installation... We did alotta mashing things down cockeyed! And the mistakes and the injuries... Lol... Good times back then! We also installed car alarms and mobile phones that were so big you had to mount them under the seat! These days we still sit on top of our phones, but that's only because we forgot to take it out of our back pocket!

 

NOT a good idea to have a device like that powered ALL the time.
With charging ports included, it might draw a fair amount of current all the time.......and run the battery down if parked for a long time.

 

It's not a good idea to leave your car door open all the time as well... But you know what? Most people don't seems to have a problem with that. Besides, a USB port that doesn't have anything plugged into it doesn't use any power bro...


"USB ports don't consume power by themselves.
Without anything plugged, they are just open-circuits. Now, if you get 1A (5W) out a USB3 port, it will usually increase the global power consumption by ~6W (depending on your power supply efficiency) which would be an increase of 2% to 5% of your computer power consumption." power - Does a computer use more electricity when charging USB devices? - Super User

 

The snazzy voltage readout on the front might use a very small amount of power constantly.

But if it gets wired to one of the car's power outlet circuits, those are off when the car is off, anyway.

 

That may be true for USB ports in a computer, if you ignore the dissipation of the USB hub and PHY functions that have to be present in ICs on the mainboard for the ports to exist, and of the computer’s power supply, which presumably would be making 5 volts anyway for other loads.

Stand-alone chargers, however, always draw at least some current unless the input voltage is shut off. One review of the device discussed here says its quiescent current is 30 mA.

Edit: PriusChat’s automatic link rewriting is broken. Find the review here:

Code:

https://www.amazon.com/gp/customer-reviews/R3A8CRPLBE8WR1/

 

That's photoshop... Zoom in close and you'll see it's not a screen, it's just plastic. As in an ebay seller's employee practicing their graphic design skills! An over-achiever creating confusion for some customers.

 

Hmm, welp, the listing description also says in English "with Digital Voltmeter Blue LED Light" and, further down, "built-in intelligent voltage monitor with LED digital display". So I guess if it turns out to just have 24.6 Photoshopped into the picture, the OP will have a pretty good case for getting a refund.

While we're waiting for Elektroingenieur to say something more relevant, 30 mA quiescent drain seems pretty comparable, if I recall correctly, to the total quiescent drain of a Prius in stock condition. Or, put another way, putting this gizmo on a permanently-powered circuit would just about double the car's quiescent drain, so probably it ought to go on an ACC or IG switched circuit.

If the thing doesn't contain a blue LED voltmeter, then I do kind of wonder where the 30 milliamps are going when nothing's plugged in.

 

Once again, you have made a gross mis-interpretation of something that you read.

A USB "power supply" is different than a USB port on a computer.

That device that was shown in the picture absolutely WILL draw some power when the charging ports are not being used.
Some to drive the display, and a tiny bit extra for the USB ports while they are not actually putting OUT any power.

 

Well THAT is pretty funny.
I was just thinking much the same thing about YOU.
And his commets were not "irrelevant", they are spot on.

It is YOU who doesn't really understand what you are talking about much of the time.

 

I have this in 2013 . Fits perfectly...

https://rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.com%2Fulk%2Fitm%2F142253325509

 

I think that using an "Add a Fuse" at the panel would be better solution and has several advantages over "poking around" and tapping a wire in the harness: (1) the OP's new outlet would be individually fused; (2) no chance of physical damage to the tapped wire or overloading the existing circuit; and (3) "poking around" means that you don't know what is on the circuit you've tapped into -- maybe you hit the airbag wiring!! Using "Add a fuse" at the panel means that you can use a circuit that has noting to with providing power to any significant system.

 

Not to clumsily and unnecessarily step into this debate/argument but isn't this true?

My admittedly limited and ignorant speculation is whether the device when powered has an automatic draw whether being used or not, if tied to a power supply that is only active when the vehicle is ON, that would bypass any worries about a power draw while the vehicle is not in operation? Wouldn't it?

If it was me, I'd just make sure I was tying it to a wire that only was active when the vehicle was on. Then not worry about whether it's drawing when the vehicle is off.