KONNWEI KW208 12V Car Battery Tester, Battery Load Tester Automotive 12V Alternator Starter Tester Digital Auto Battery Analyzer Charging Cranking System Tester for Car Truck Marine Motorcycle Boat

Amazing for the price. You won’t be disappointed! Works straight out of the box, with no batteries or charging needed since it’s powered directly from the car.The instructions aren’t the best, so for those who might not know: connect it to the car by attaching the Positive (red) clamp to the positive terminal of the car battery first, then connect the Negative (black) clamp to the negative terminal on the battery. It can test batteries both in and out of the car.The device will power on once connected, and you get three options for testing the battery with step-by-step instructions.The three options are Battery Test, Cranking Test, and Charging Test. The Battery Test will determine the health of a battery, the Cranking Test will measure the battery's ability to start the engine, and the Charging Test will measure the voltage of the battery while the vehicle is running to determine if the battery and alternator are working.If you think you have a bad alternator, use this device first and run through the tests. It provides straightforward results (as shown in the photo) that tell you if the battery is good, needs to be replaced, or if the alternator has no output.Couldn’t recommend this device enough

Caveat: I am NOT a mechanic by any means! But I can follow simple directions and open a car's hood (or "bonnet" for our friends in the UK...). If you can do these things, you can use this device. I attached it to my car battery after reading the directions (which are printed in like 3-pt type so be aware of that) and watching a couple vids of the device reviewed and used. The device quickly reported that my battery was on its last legs (as I suspected from the hard starts), leading me to taking it in to get a new battery installed. For about $25 it seems to be a versatile device, too, supporting three distinct kinds of tests for your battery and alternator's performance. I've paid more (a lot more at times) for things of far lesser utility to me than this, so you are in good shape having one around.

This is my first venture into testing batteries. Wasn't sure if this particular tester was a good judge of battery condition. I first tested 2 12v Marine batterys, 10 yrs old, knowing at least 1 was not holding a charege very well. Both batteries first test showed Charge-Retest. After this they both tested as Replace, not surprised. I took it one step further and used them as a power supply for my 2000w inverter. Both batteries worked ok but dropped to 11.9 volts on a 100w load after only a couple minutes and lasted about 2 hours, eventually dropping to 11 volts. My inverter will cut off at 10.5 volts. I purchased a new 12v Marinine/RV battery, lower CA and AMP hour rating. I again hooked up to my inverter on 100w load and tested. This battery lasted 5 hrs on the load and never got lower than 12.3 volts. With this test I would say this is a good tester and recommend it.

I bought this primarily because I had been dropping off some used motor oil to my city collection center and saw a pallet of used batteries submitted for recycling. Among them was an Optimus Blue Top combination starter and deep cycle battery commonly used in boats. This is about a $400 battery so I thought what the heck and took it home to see if it would hold a charge. Sure enough it charged up just fine and seemed ok. However, I know a battery can show full charge but still not have the cranking amps. This is a spiral agm battery so I set the unit accordingly and tested it. It tested good on both CCA and MCA. So lucky me. I also have a car that I just put a remanufactured battery in (bad idea, don’t waste your money) but the cranking rate seemed slow. No CCA rating was printed on the battery so I just guessed 550 and tested it. It tested ok but not great. Lastly, I have an old jeep that remarkably has had the same battery in it for over 15 years. If I kept on a 1 amp charger during periods of no use (a week or more) it will still start the car just fine and continue to start it if in daily use. The load tester showed to replace the battery. That battery is no going thru several repair cycles with a 5 amp NOCO charger. I’ll let you know how it works out.It also worked fine for testing the alternator.In summary, for a diy’er, I think this is a fine tool. It is solidly made, the wires are heavy enough and long enough, and the clamps are very well contructed and hold tight. One reviewer indicated the instructions are microscopic and very broken english and was kind enough to give some alternate instructions. However, it is very intuitive to use so once you’ve done it, you’ve got it. For $25, go for it.P.S. - i highly recommend NOCO Chargers. A touch on the pricey side but very high quality.

Positives:-Works as intended, providing accurate battery readings.-Easy-to-navigate menu for hassle-free operation.-Compact design allows for easy storage in the car's compartment.-Essential for regular battery checks, especially for those experiencing battery issues.Negatives:-Virtually no drawbacks; it effectively delivers on its promises.The KONNWEI KW208 12V Car Battery Tester has proven to be an indispensable tool in my car maintenance routine. As someone currently facing battery problems, I rely on this device to regularly check my battery's status, and it has been a lifesaver.The tester works exactly as intended, offering clear and accurate readings that help me determine when I need to charge my battery. The menu is straightforward, making navigation quick and simple, even for those who may not be tech-savvy.Its compact size is another standout feature; it fits snugly in my car's storage compartment, ensuring that it's always on hand when I need it. While there are no notable negatives to mention, it’s worth emphasizing that it fulfills its purpose effectively. Overall, the KONNWEI KW208 is a reliable and practical investment for anyone looking to keep their car battery in check.

Easy to use...works well