How to Test an Automotive Ignition Coil?
1 Answers
There are three methods to test an automotive ignition coil: 1. Visual Inspection: Examine the ignition coil visually. If the insulation cover is cracked or the outer casing is damaged, it may absorb moisture and lose its ignition capability, requiring replacement. 2. Primary and Secondary Winding Open Circuit, Short Circuit, and Grounding Tests: (1) Resistance Measurement Method. Use a multimeter to measure the resistance of the primary winding, secondary winding, and additional resistor of the ignition coil. The values should meet technical standards; otherwise, it indicates a fault and requires replacement. (2) Test Lamp Method. Connect a test lamp to the two terminals of the primary winding. If the lamp does not light, it indicates an open circuit. To check for grounding faults, connect one end of the test lamp to the primary winding and the other end to the casing. If the lamp lights, it indicates a grounding fault. Short circuit faults are not easily detected with a test lamp. 3. Spark Intensity Test: To check the high voltage generated by the ignition coil, it can be tested on a test bench in conjunction with a distributor. Adjust the discharge electrode gap to 7mm, start at low speed, and once the ignition coil reaches operating temperature (60~70°C), adjust the distributor speed to the specified value (generally 1900r/min for four- and six-cylinder engine ignition coils, and 2500r/min for eight-cylinder engine ignition coils). If it can continuously produce blue sparks within 0.5 minutes, the ignition coil is in good condition.
