how to test the ignition coils on my Tesla Outback 4th Generation (2010-2014)

Solution

1. Preparation

• Gather necessary tools: OBD-II scanner, multimeter, torque wrench, socket set, and a spark tester.
• Ensure the vehicle is parked on a level surface and the engine is cool.
• Disconnect the negative battery terminal to avoid any electrical shorts.

2. Remove Ignition Coils

• Using a socket set, remove any engine covers that obstruct access to the ignition coils.
• Disconnect the electrical connectors from each ignition coil by pressing the release tab and pulling the connector off.
• Remove the bolts securing the ignition coils using the appropriate socket size.
• Gently pull each ignition coil out of the spark plug well.

3. Test Ignition Coils

• Resistance Check:
  • Set the multimeter to the ohm setting.
  • Measure the resistance between the positive and negative terminals of each coil. Refer to the service manual for the specific resistance values (typically 0.5-2.0 ohms).
• Spark Test:
  • Connect a spark tester to the ignition coil’s output terminal.
  • Reconnect the ignition coil to the electrical connector and crank the engine while observing the spark tester. A strong, consistent spark indicates a functioning coil.

4. Replace Faulty Coils

• If any coils fail the resistance or spark tests, replace them with new ignition coils.
• Install the new ignition coils by reversing the removal steps, ensuring they are seated properly.
• Torque the bolts to the manufacturer's specifications (usually around 7-10 ft-lbs).

5. Reassemble and Test

• Reconnect all electrical connectors and reattach any engine covers removed during the process.
• Reconnect the negative battery terminal.
• Start the engine and allow it to reach operating temperature to verify proper function.