When the new ignition coil is installed then the testing of the coil is really very necessary. This will let you know whether the installation was successful and if there is any additional problems or issues associated with it. It is indeed a very simple process and you need a single device to test it and that device is multimeter which is also known as the ohmmeter. Coils can be considered as the watertight component that are generally sealed and they are not a repairable item. Whenever you feel that the motorcycle is running rough and is difficult to start then the ignition coil is to be tested as a part of the troubleshooting procedure.
The main purpose of the ignition coil is to step up the low battery voltage to high which is needed to spark plug. It is advised to test the coil when the coil is hot. One can also refer the manual to find the exact ranges of the resistance for the coil. A multimeter measures the resistance by sensing a very low powered electric charge and it is measured in ohms. Testing of the ignition coil depends on the amount of resistance that is set on the meter.
Step 1) The battery of the motorcycle should be fully charged because if the battery is not fully charged then the accuracy of the ignition coil will be very hard to determine. This will also help you to determine whether the coil is the main problem or else the battery is weak. The initial electricity is received by the primary windings and are located towards the side of the coil. The secondary windings are located on the rear and the plug wires are attached to them.
Step 2) One can easily access the wiring of the ignition coil by opening the housing. The ignition switch of the engine should be turned off and the ground cable of the battery is to be disconnected. In order to access the spark plugs and coil, remove the bike seat as well as the fuel tank. There are some bikes where the ignition coil is located under the flywheel and those are mostly mopeds.
Step 3) The plug cap is to be removed for the test, if it is not removed then it can make your test inaccurate. Sometimes the cap itself can add extra resistance to the results. The result of the resistance should be very low. It should be 0.5 to 1.5 ohms. The resistance can be measured from the ground terminal wire or the primary wire. The primary wire is the one that is going towards the CDI points or CDI box. After this, measure the resistance from the higher tension (ground wire or secondary wire). The result for this should be higher around 7000 to 14000 ohms.
Step 4) If the final result of these wires is not between the indicated numbers then it shows that the ignition coil is bad. One can further analyze the results by using machines that can test the coils under pressure. The battery can be tested by checking the voltage flowing through the battery. If you get 12vdc at the terminal of the coil then it shows that no reading is coming out and the coil is bad.
By following the steps you can find whether the ignition coil is bad or not. If it is bad then you can either replace the coil or consult the mechanic with the readings that are recorded.
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