Knowing this allows adjustments to be made via manipulation of the distributor cap to make the spark plugs fire before or after the piston has reached the top dead center, depending on the malfunction or issue that needs to be fixed. By aiming this strobe light in the proper place, usually the crankshaft pulley, you will be able to read the degree markings on it, which are indicative of where the crankshaft is in its rotation and the respective pistons. Inductive timing lights, when connected properly to the cars engine and battery, detect the electricity every time the plug fires, and every time the plug fires, the timing light shoots a beam of light. The light is powered by the vehicle it is being used to test. The light can be a stroboscope that may use a simple neon lamp or a xenon strobe lamp that provides brighter light and better use in daylight or in shop lighting. Timing lights are diagnostic tools used to observe ignition timing in vehicles with distributors and are available as self-contained units or as a part of a more comprehensive engine analytical tool. See Your Cars Diagnostics More Clearly With Automotive Timing Lights
