Home Auto How to Test 12 Volt Ignition Coils

How to Test 12 Volt Ignition Coils


An automobile ignition coil acts as a transformer, having a primary and secondary bundle of wires that create and send an electrical charge to the spark plugs, causing them to fire. While ignition coils will generally last for the life of a vehicle, faulty spark plugs or spark plug wires can send irregular voltage surges through the ignition coil, causing the coil to burn out. You can test a 12-volt ignition coil for effectiveness by checking the resistance of its wire windings with a multimeter.

Step 1

Disconnect your engine’s main negative battery cable with a wrench.