As our device with 3 meter cable, it will be a convenient , should you not have jump starter motor -LRB- or Lead-acid battery -RRB- on hand, and the device can also get the 12v power supply from cigarette lighter of another cracking car. Just the Cigarette lighter plug to this car and insert into 16 pin plug to the OBD port of the car you want to replace battery. And now you can the battery. : 1. When working with the vehicle 's battery, review all the battery manufacturer 's and vehicle manufacturer 's safety instructions, warnings and directives regarding battery, removal and replacement. . . The vehicle 's physical phenomenon system is power from memory saver through the OBD connection. Therefore, the vehicle 's battery connectors are electrically and should be covered with an insulator to prevent the connectors from touching metal or each other and causing a truncated circuit. After each use, the memory saver and use a baked cloth to wipe all dirt or oil from the connectors and the cable. . . During battery replacement, DO NOT on -LRB- ignition -RRB- the car, which its older battery is disconnected and brand-new battery not yet finished replacement. As well, DO NOT the central on `` ACC ON ''. If not, the fuse of the memory saver probably out, due to full amp and overload. Troubleshooting :. The 12V DC plug of memory saver should be correctly attached 12V power, if not, the ruddy led lightweight on the plug will not lightweight up ; that means no power signal from the power source or with incorrect polarity connection. the power source from another car, then check whether the car 's Cigarette Lighter on cracking condition or not. the power source from a jump starter motor, then verify if the cause is from the contact. If the power source is from an alternate 12V Lead-acid battery, then whether the polarity exact or not. . . The memory saver 12V DC plug an 8 amp fuel.