How do you check voltage on an ignition coil?
Connect your multimeter to the positive terminal or pin of your coil, and to the high output terminal that goes to the spark plug.
Most ignition coils should have a secondary resistance falling somewhere between 6,000 to 10,000 ohms;however, refer to manufacturer specifications for the correct range..
How do you test a 12 volt coil?
How to Test 12 Volt Ignition CoilsDisconnect your engine’s main negative battery cable with a wrench.Pull the main ignition coil wire, the one that leads to the distributor, off the coil. … Turn on the multimeter and set it to the “ohms” function.More items…
How does a coil increase voltage?
When a source of AC is connected to one of the coils, that coil creates a magnetic field that expands and collapses in concert with the changing voltage of the AC. In other words, as the voltage increases across the coil, the coil creates an expanding magnetic field.
How can you tell if an ignition coil is bad?
Signs of a Bad Ignition CoilIlluminated Check Engine Light. With most modern vehicles, a faulty ignition coil is enough to turn on the Check Engine Light. … Misfiring Engine. If an ignition coil is not working properly, your engine will likely misfire. … Hard Starts. … Worsening Gas Mileage. … Diminished Power. … Sudden Backfires.
Do you need a resistor with a 12 volt coil?
When a 6 volt ignition system is converted to 12 volts either a 12 volt coil must be installed or a resistor installed in the circuit to reduce the coil voltage to 6 volts. The resistor regulates the voltage, keeping it at 6 volts, allowing the original 6 volt coil to be used in a 12 electrical system.
What does a bad ignition coil sound like?
If you try to start your engine up and you hear a spluttering sound repeatedly, then you are likely experiencing an engine misfire that can be attributed to a bad ignition coil. You may still be able to drive your vehicle, but you will hear a lot of strange noises and even feel jerkiness as you accelerate the vehicle.