Circuit/System Testing

Ignition OFF, disconnect the harness connector at the appropriate T8 Ignition Coil.
Engine Running.
Verify the appropriate scan tool Ignition Coil Control Circuit Low Voltage Test Status does not display Malfunction.
- If Malfunction is displayed
1. Ignition OFF, disconnect the X2 harness connector at the K20 Engine Control Module.
2. Test for infinite resistance between the control circuit and ground.
  - If less than infinite resistance, repair the short to ground on the control circuit.
  - If infinite resistance, replace the K20 Engine Control Module.
- If Malfunction is not displayed
Verify the appropriate scan tool Ignition Coil Control Circuit High Voltage Test Status does not display Malfunction.
- If Malfunction is displayed
1. Ignition OFF, disconnect the X2 harness connector at the K20 Engine Control Module.
2. Test for less than 1 V between the control circuit and ground.
  - If 1 V or greater, repair the short to voltage in the circuit.
  - If less than 1 V, replace the K20 Engine Control Module.
- If Malfunction is not displayed
Ignition OFF, install a 3 A fused jumper wire between the control circuit terminal C and ground, engine Running.
Verify the appropriate scan tool Ignition Coil Control Circuit Low Voltage Test Status displays Malfunction.
- If Malfunction is not displayed
1. Ignition OFF, remove the fused jumper, and disconnect the X2 harness connector at the K20 Engine Control Module.
2. Test for less than 2 Ω in the control circuit end to end.
  - If 2 Ω or greater, repair the open/high resistance in the circuit.
  - If less than 2 Ω, replace the K20 Engine Control Module.
- If Malfunction is displayed
Test or replace the T8 Ignition Coil.