Wirthco Engineering Inc 20395 Battery Life Preserver, Black

This elegantly conceived automatic cutoff switch is working very well for me. It shuts down my car's battery once its voltage drops below 12V, preserving essential starting power. Today’s cars consume small amounts of electrical energy for clocks, alarms, keyless entry systems and so on, even when parked. This can empty a battery if the car is not driven for more than a month or so. Since mine does not get used for extended periods I’ve had a dead battery more often than I care to remember. Problem solved!Installing this beautifully made device was a breeze. It is completely sealed and will likely outlast my car noting that it is fully electronic rather than electromechanical, hence zero wear and tear. All electrical pathways and the two battery clamps are copper alloy, a nice touch.There are two versions of this switch. The new version going forward, in production since April 2016, works as a conditional shutoff / complete shutoff whereas the old one was conditional shutoff / always on. WirthCo, the manufacturer, made this change after consumers got confused about not being able to disconnect the battery with the wireless remote. They expected this would be part of its function. Now it is, empowering scenarios requiring manual shutoff such as boats, caravans, or theft prevention.(I found this out after writing to WirthCo because I could not make sense of the bipolar nature of the reviews here, with almost nothing in the middle. The company went to great lengths to explain the details to me.)Summing up, well thought out, well made, great customer care, and the price is right.

Worked great initially. After a few weeks performance became erratic and it would not reconnect the battery. I had to open the hood and remove the device to start the vehicle. The second time this happened was at night in a dark parking lot in a not so great part of town. I've since replaced this with a product by another manufacturer.

===== UPDATE: 2017-10-21 =======Ordered a replacement unit and sent back the original one. Tested the second unit on "the bench"" before installing and this one works as advertised. A picture is worth a thousand words (see attached). On the picture you can see that I hooked the unit up to a variable output transformer and two digital multi meters.I started feeding the relay unit with 12.40 Volts while measuring the voltage at BATTERY+ terminal and voltage out at CABLE+ terminal.One of the multi meters is used to confirm/verify the voltage coming from the variable transformer.The LED light on the unit is blinking BLUE during normal operation.Then I gradually lowered the voltage fed to the unit simulating a battery drain condition.As soon as the voltage coming into the unit dropped to 12.0 Volts the LED light on the unit started to blink RED.About 60 seconds after the LED light turned RED the Relay on the unit shut off the power to CABLE+ terminal, but there's about 800 milli-volts of leakage on the CABLE+ terminal as can be seen on the picture.Then I raised the voltage to simulate a battery rest (recovery) and the relay remained OFF while the LED continued to blink RED( it's a good thing).Using the remote I hit unlock button, the LED turned BLUE and voltage is restored to the CABLE+ terminal as expected (12.4V).I also measured current draw using an extremely sensitive, specialized CLAMP on Ammeter and it measures about 5 to 10 milli-amps. There's a Radio receiver that's awaiting commands from the remote key-fob, so a small amount of current draw is expected.I performed various combinations of tests such as manually disconnecting (which turns LED to YELLOW blink) and the voltage leak is again 800 milli volts.I repeated these tests for several hours throughout the night and next day to verify the results. When the voltage drops to 12.00V or below for about 58 seconds the unit disconnects the power. If the Voltage drops to 12V or below for just a few seconds and then if it goes above 12.00V then the LED changes back to BLUE and the unit does not disconnect power (it's a good thing). Again, once the battery voltage drops to 12.00V. the LED changes color to RED blinking and if it continues to stay at 12V or below for about 1 minute it cuts the power and you have to use the rest switch or the remote unlock button to reconnect the battery. You can put the unit in a bypass mode ( LED is OFF) using the reset switch.*** Here are some IMPORTANT CONCERNS ***:If you manually disconnect the power using the remote, you can not restore the power using the reset switch on the unit!!! So, if you loose your remote, or your remote control suddenly ran out of battery then you will be stranded. Keep the spare remote somewhere in your vehicle as a backup. You can't put the unit in a bypass mode using the switch if you manually disconnected the power using the remote control!Also, if you have a remote start installed on your vehicle (such as Viper Remote start), when you restore the power the remote start won't work the first time after you restore power. You have to use your key to start the vehicle. The remote start then synchronizes and resumes to work on subsequent starts until the battery is disconnected again.Hope this review helps others as I've spent considerable amount of time testing the two units I received over several days.Finally installed the product on my vehicle after extensive testing. I will try to update the review in the future for long term reliability.====== ORIGINAL REVIEW BELOW: ===========I should have tested this UNIT on an external battery before installing it. The unit does not disconnect the power even when YELLOW LED is flashing.*** WHEN YELLOW LED IS BLINKING I SHOULD NOT BE READING OVER 12 VOLTS BETWEEN GROUND AND TERMINAL MARKED CABLE+ ***The wiring layout is very simple, The remotes that i received were already programmed/synchronized with the module and the sticky tape on the buzzer was already peeled off as if it was mounted before. After I started the install project I realized I'm missing a small bolt for positive terminal brass connector. It appears this unit was used previously and repackaged after refurbish inspection.I removed the unit from my vehicle and tested it on a jump start battery pack as follows;connected terminal marked BATT+ to RED (positive) Alligator Clip on battery jumpstart pack.Connect the thin black wire to the BLACK( negative) alligator clip of the battery jumpstart pack.The unit powers on and YELLOW LED blinks. At this point when YELLOW LED is blinking it means the circuit is open(disconnected) and when I connect the RED probe of my multi-meter to the terminal marked CABLE+ on the unit and the black probe to the BLACK alligator of the jumpstart battery I SHOULD NOT BE READING 12.53 VOLTS!!! The circuit should be OPEN (it should be disconnected)!!!Using the remote I reconnected the unit, it beeped twice, BLUE LED started blinking, the multimeter reads over 12V.Using the remote I disconnected the unit, the unit beeped, YELLOW Led started blinking, the multimmeter still reads over 12V between ground and terminal marked CABLE+ .I tried resetting, trouble shootings, blah blah blah, NFG (No friggin' Good)I ordered another unit and should arrive on SUNDAY. I will inspect closely and TEST BEFORE INSTALLING it on the vehicle.IN THEORY:This is supposed to be a great unit, when battery voltage drops to 12V for 30 seconds or longer it will automatically disconnect the battery so the battery doesn't die completely.This unit won't disconnect the battery while the vehicle is running (a good safety feature).Wireless remote is convenient.The optional reset switch is good to have in case you lose the remote.But POOR QUALITY CONTROL SUCKS!!! (Note: it is possible that AMAZON has received a defective unit that was returned, then Amazon may have tested the unit for power on, beep, etc and erroneously decide the unit is not defective and sold it to the guy (me) next in line. In fact the relay on the first unit was defective.

This device saved me from having to replace vehicle I hope to get a couple more years out of. I have a 2003 Chevy Venture with over 300K miles but it still runs great! But I had a problem I couldn't afford to fix and there was no easy solution. The proper repair would have been a new ECM costing upwards of $700 installed. What was happening was something failed in the alarm system so what was happening was that no matter what I did, when I turned the vehicle off, the alarm would blow the hor and flash the lights. It got so bad I pulled the horn fuse to stop from bothering the neighbors but eventually the battery would drain and I would have to jump start it. This went on about a month while I tried fixing it and researched the problem that others had like this (it's a very common problem on my vehicle).I finally decided to add a manual battery disconnect but this would mean opening the hood every time I stop it or run it.Then I found this device and my problem was solved. I just kill the battery with the remote when I stop or use the remote to power up the battery when it was time to go. This device is a very talented addon I would recommended for ANY 12v vehicle that isn't used often and my battery has been like a new one ever since I installed this. You need to know the recommended stud extenders make the install job much easier so you should get them when you get one of these. Also, there is a pretty flimsy ground wire and without that wire getting a solid ground connection at all times, you will be dead in the water. So beef up the little black ground wire and make sure it has a very good grd connection and you will be amazed at how well this works!

Updated Review: Died on June 4, 2018 (purchase May 27, 2017). So it died almost exactly one year later. Very disappointing.Original Review: Works great, seems quite reliable and effective so far. Great for long term storage of my car, where the battery is impossible to get at (so conventional battery disconnects were not practical).