ProMax HD Car Truck 12V Battery Vehicle Start Protector

I bought this as a last resort to overcome a phantom battery drain on a Toyota Prius (spit) that one dealer and two independent mechanics failed to solve.It has performed perfectly. If the car battery falls below the shut off voltage, further drain is stopped. The only inconvenience is that the remote won't work so you have to go retro and open the door with a key. Once the ignition is turned on the battery magically springs to life.The worst part of the installation was finding terminal adapters to convert the Prius from small posts to those the rest of the world uses.I almost wish I needed another one just because they work so well. T

I have a 1993 GMC 2500 Vandura that has a short I can not locate. At first I thought it was just bad battery or battery connection. After replacing the battery and cables, everything was fine for 3 days. Then I found myself with a completly dead battery in a mall parking lot during a bitter cold spell.I have used this device in the past in a 1981 BMW 733i which had a similar power drain issue and it worked.So I bought the HD version of the ProMax for the Van, installation took all of 15 minutes. My battery still gets drawn down when left at the airport for several days, BUT never below the 11.7volts threshold that the ProMax trips at! I just step on the brake to create a current draw that the ProMax can detect and it reconnects the battery circuit allowing more then enough reserve energy to start the big 550 V8.This device is a life saver! It it Ruggedly built, of the best materials, easily installs in minutues, and will never leave you stranded due to a dead battery again!

Over the years I have had a 97 Pontiac Transport, a 98 Transport, a 2003 Chev Ventura, a 2001 Camaro, a 98 Chev Silverado, and now a 95 Sivlerado. All these GM autos had the same problem. After about 3 to 4 weeks, if not started, the computer runs the battery dead. I sometimes do not use my Chev truck for 2 or more weeks and hate the dead battery so I bought this for well over $100. I left my dash compass with the tiny LED light plugged in so I could see when it disconnected. After about 16 days it was out so I flashed my headlight on & off & could hear the Priority start reconnect. Although this MIGHT work on a little puddle jumper car with a 1 liter engine, but it cranked my Chev 350 CID [5.7 Liter] engine over slowly about 2 rounds and then DEAD! I jumped it and used it for a couple days & then let it sit about 3 weeks & sure enough,, it had disconnected. I flashed the light switch, heard it reconnect, and turned engine over slowly about 2 rounds,, Then DEAD! When your battery is about 90% dead & the engine has not been running for a couple weeks IT WILL NOT START. And if you were in a northern climate like Wisconsin where I came from and it were 5 above zero,, it is a worthless piece of junk. It is too homely to use for a paperweight & my time window has closed to return it so I am out over $100. I now installed a wonderful battery shutoff for under 10 bucks. Get yourself one of those neat shutoffs with the little green plastic knobs, install that on either the positive or negative side of the battery, loosen the green knob a round or 2, and when you want to go, tighten the green knob, jump in, start her up and GO. If you have over a hundred bucks to throw away, buy this useless contraption and you will be walking.

unit works well

I work out of my vehicle 10 months out of the year. I have a Laptop, 2 GPS units, strobe light, 2 phone chargers running off of the small battery in my Ranger. This unit has saved me from having to jump start at least 6 times since I purchased it. Installation was not difficult for my application. If you have issues with dead batteries like I did, this is a god send. The thing I like most is that you don't have to open the hood. When you turn the key and it doesn't start... just wait a few seconds and the disconnect resets and then turn the key again and she fires right up. Awesome product for older vehicles that do not have a low voltage disconnect built in.

The next morning after I installed it and a new battery into my jeep, I realized I had left my a/c-air pump switch on when it had no battery. It got triggered that evening and in the morning all I had to do was tap the break pedal and it Reengaged. Very nice 👍🏻

I have a C5 Corvette with some added electronics that run after shutoff (camera, led on a built in usb charger). If I let the car sit for a couple weeks it kills the battery. This solves the issue 100% and I don't have to mess around with a cutoff switch.Had a little difficulty with my first install, must have been a bad ground even though it looked OK. After applied a little electronic grease and tightened things up it was good to go. I tested by leaving my headlights on 2 different times and it worked perfect. I haven't yet let it sit for 2-3 weeks to test a small discharge, but I have no reason to think it wouldn't work the same for that.I wanted a better solution than a battery disconnect (even in-cabin is not that appealing to me- and installation is an added hassle), and this worked.

UPDATE: Sent faulty unit back to the company six weeks ago and never heard back. At all. Emailed to follow up, and they have never replied. Terrible customer service, and you cannot return or refund this item through Amazon. AVOID!Great product in theory, but this is the second one to fail. The first was about two months out of warranty, this one is only 6 months old. Completely drained my battery, ended up buying a manual battery disconnect. It's a bit more of a hassle, but at least I know if the battery is actually safe. I'll update the review once I've heard back from the company about a refund...