Circuit/System Testing

Ignition OFF, disconnect the harness connector at the B34 Engine Coolant Temperature Sensor.
Ignition OFF and all systems OFF. It may take up to for 2 minutes for all vehicle systems to power down. Test for less than 2 Ω between the ground circuit terminal 2 and ground.
- If 2 Ω or greater
1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for less than 2 Ω in the ground circuit end to end.
  - If 2 Ω or greater, repair the open or high resistance in the circuit.
  - If less than 2 Ω replace the K20 Engine Control Module.
- Go to next step: If less than 2 Ω
Ignition ON, test for 4.8 - 5.2 V between the Engine Coolant Temperature Sensor power supply circuit terminal 1 and ground.
- If less than 4.8 V
1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for infinite resistance between the power supply circuit and ground.
  - If less than infinite resistance, repair the short to ground on the circuit.
  - If infinite resistance
3. Test for less than 2 Ω in the power supply 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 greater than 5.2 V
1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Ignition ON, test for less than 1 V between the power supply circuit and ground.
  - If 1 V or greater, repair the short to voltage on the circuit.
  - If less than 1 V, replace the K20 Engine Control Module.
- Go to next step: If between 4.8 - 5.2 V
Test or replace the B34 Engine Coolant Temperature Sensor.