Problem is you now need to remember to keep THAT thing charged and in the car.. and I'd bet that unless you constantly hose your car battery you will only need this device when you discover that its been sitting for 4 years in your car and is itself gone flat.

If anything, why not a hand-cranked dynamo of old-school type that gets regulated to 12 volts? That never fails.

 

my biggest concern about these things is if it actually has the power to start a truly dead battery. I was once looking at a used car and when i went to start it, the battery was dead. the salesman brought out a strong jump starter and it wouldn't jump it off. He said the jumper was topped off, but who knows.

 

Not enough current.

 

Just look after the battery in the vehicle, change it before it fails, ie: the first time it shows any signs of losing power. No need to be buying junk to carry around that may or may not work when you need it.

 

Actually the whole reason I got this was to be able to at least open the frunk when the battery is dead, or if I stupidly close the frunk when the battery is disconnected, like how I did it a few months ago. Ever since then I get so paranoid when I close the frunk, EVERYTIME!

 

unfortunately, most batteries today give no warning for failure. Starts perfect one time...nothing the next. I spent 5 hours waiting for roadside assistance in a remote Canyonlands campsite learning that. That was on a less than 2 year old battery in my "11 Tacoma.

 

can you not plug in plug-to-wall battery tender to the cig lighter and use that power to open the frunk? i keep my battery tender in the glove compartment for this very reason.

 

I haven't tried it but there have been reports that just a battery tender won't provide enough juice to open the trunk - you need a battery hooked up to the red terminal in the fuse box.

 

I live in an apartment building so the car is parked in the basement carpark where there's no easy access to electricity. When it happened to me last time, I had to pull the battery out from my other car and tap it to the fuse box and door lock...etc, while I was in a panic mode late at night during a rain storm! Now that I've done this it all sound so easy now

I received the battery pack for the cable was damaged. The dealer was nice enough (from China!) to sent not one but TWO extra cables which just arrived, except that my car was dropped off at the bodyshop just this morning for a complete nip tuck! Oh well, I guess I can only test this thing in about a month time.

 

So that fuse-box post provides power to more than just the frunk release circuit? That seems silly, since the point of that post is to pop the frunk so you can get to the battery to jump/charge it. I'd expect that post to not have to power the larger electronics, and the power to run a motor for the frunk release.. how many amps does that draw?

 

Not exactly sure, but I'd be surprised if that crank generator could generate enough. There's a home science project for someone.