<br>This battery tester provides the technician, professional and DIYer, with critical information about battery health status by identifying battery and charging problems quickly and accurately. <br><br> <b>Checking the Dynamo: </b>Connect the testing device. Start the engine and switch off the headlights, radio etc. Star the engine again and switch on the headlights, radio etc. In both cases, then green signal LED "GOOD" should shine. The red signal LED " Defective" will start to shine if the dynamo in bad condition. If the situation happen, please go to local car workshop in your earliest time. <br> <br><b>Checking the Charging Level: </b> Switch on the headlights for 1-2 minutes, then switch off. Remove the cable clips from the battery, wait approx. 10 mins then switch the testing device on again. A signal LED will shine according to the charging status of the battery indicating " Full" " Half-full" or "Very low charge" .<br> <br> <b>Battery Start Capability: </b>The battery needs to be charged up to the maximum. Remove the connection of the ignition coil then connect the testing device. Try to start the vehicle using the key in the ignition switch. The engine cannot start (interrupted ignition). When the green signal LED "Battery OK" starts to shine, the charging status of the battery is ok. <br> <br><b>Start the Battery Capability Load: </b>Switch to the loading test mode, then start the engine. <br> <br><b>Full: </b>six-five LED will be shine ; <br> <br><b>Middle: </b>four-three LED will be shine ; <br><br> <b>Low: </b>two-one LED will be shine, if no LED shine it means the battery capacity is very low, please charging the battery or change the battery. <br> <br><b>Swich to the left is Battery Load Test Mode</b><br> <br><b>Swich to the right is Battery Charging Test Mode</b><br><br><b>Note: If the battery is not in good condition, the signal lamp "Battery OK" will start to go off and charging status of the battery LED will not loght up. </b>