Circuit/System Testing

• If less than 2.0 V 

1. Ignition/Vehicle - Off
2. Disconnect the appropriate electrical connector: K20 Engine Control Module
3. Test for infinite resistance between the test points: Signal circuit terminal 1 @ Component harness & Ground
   • If less than infinite resistance - Repair the short to ground on the circuit.
   • Go to next step: If infinite resistance
4. Test for less than 2 ohms between the test points: Signal circuit terminal 1 @ Component harness & The other end of the circuit @ Control module harness
   • If 2 ohms or greater - Repair the open/high resistance in the circuit.
   • If less than 2 ohms - Replace the component: K20 Engine Control Module

• If greater than 3.0 V 

1. Ignition/Vehicle - Off
2. Disconnect the appropriate electrical connector: K20 Engine Control Module
3. Ignition - On / Vehicle - In Service Mode
4. Test for less than 1 V between the test points: Signal circuit terminal 1 @ Component harness & Ground
   • If 1 V or greater - Repair the short to voltage on the circuit.
   • If less than 1 V - Replace the component: K20 Engine Control Module

• Go to next step: If between 2.0 and 3.0 V 

• If less than 2.0 V 

1. Ignition/Vehicle - Off
2. Disconnect the appropriate electrical connector: K20 Engine Control Module
3. Test for infinite resistance between the test points: Signal circuit terminal 2 @ Component harness & Ground
   • If less than infinite resistance - Repair the short to ground on the circuit.
   • Go to next step: If infinite resistance
4. Test for less than 2 ohms between the test points: Signal circuit terminal 2 @ Component harness & The other end of the circuit @ Control module harness
   • If 2 ohms or greater - Repair the open/high resistance in the circuit.
   • If less than 2 ohms - Replace the component: K20 Engine Control Module

• If greater than 5.5 V 

1. Ignition/Vehicle - Off
2. Disconnect the appropriate electrical connector: K20 Engine Control Module
3. Ignition - On / Vehicle - In Service Mode
4. Test for less than 1 V between the test points: Signal circuit terminal 2 @ Component harness & Ground
   • If 1 V or greater - Repair the short to voltage on the circuit.
   • If less than 1 V - Replace the component: K20 Engine Control Module

• Go to next step: If between 2.0 and 5.5 V 

• If less than 4.5 V 

1. Ignition/Vehicle - Off
2. Disconnect the appropriate electrical connector: K20 Engine Control Module
3. Test for infinite resistance between the test points: Signal circuit terminal 3 @ Component harness & Ground
   • If less than infinite resistance - Repair the short to ground on the circuit.
   • Go to next step: If infinite resistance
4. Test for less than 2 ohms between the test points: Signal circuit terminal 3 @ Component harness & The other end of the circuit @ Control module harness
   • If 2 ohms or greater - Repair the open/high resistance in the circuit.
   • If less than 2 ohms - Replace the component: K20 Engine Control Module

• If greater than 5.5 V 

1. Ignition/Vehicle - Off
2. Disconnect the appropriate electrical connector: K20 Engine Control Module
3. Ignition - On / Vehicle - In Service Mode
4. Test for less than 1 V between the test points: Signal circuit terminal 3 @ Component harness & Ground
   • If 1 V or greater - Repair the short to voltage on the circuit.
   • If less than 1 V - Replace the component: K20 Engine Control Module

• Go to next step: If between 4.5 and 5.5 V 

Signal circuit terminal 7 & Ground

• If 0.00 V 

1. Ignition/Vehicle - Off
2. Disconnect the appropriate electrical connector: K20 Engine Control Module
3. Test for infinite resistance between the test points: Signal circuit terminal 7 @ Component harness & Ground
   • If less than infinite resistance - Repair the short to ground on the circuit.
   • Go to next step: If infinite resistance
4. Test for less than 2 ohms between the test points: Signal circuit terminal 7 @ Component harness & The other end of the circuit @ Control module harness
   • If 2 ohms or greater - Repair the open/high resistance in the circuit.
   • If less than 2 ohms - Replace the component: K20 Engine Control Module

• If greater than 5.5 V 

1. Ignition/Vehicle - Off
2. Disconnect the appropriate electrical connector: K20 Engine Control Module
3. Ignition - On / Vehicle - In Service Mode
4. Test for less than 1 V between the test points: Signal circuit terminal 7 @ Component harness & Ground
   • If 1 V or greater - Repair the short to voltage on the circuit.
   • If less than 1 V - Replace the component: K20 Engine Control Module

• Go to next step: If greater than 0.00 V and less than 5.5 V 

• B52 Heated Oxygen Sensor - Water intrusion @ Harness Connector
• Coolant consumption - Refer to: Coolant in Combustion Chamber , or Coolant in Engine Oil
• Engine - Vacuum leak
• Evaporative Emission Canister - Saturated with fuel
• Exhaust System - Cracked/Leaking/Loose Clamps/Missing components/Restricted - Refer to: Symptoms - Engine Exhaust
• Fuel - Contaminated/Poor Quality - Refer to: Alcohol/Contaminants-in-Fuel Diagnosis
• Fuel Injectors - Restricted/Stuck - Refer to: Fuel Injector Diagnosis
• Fuel Pressure - High/Low - Refer to: Fuel System Diagnosis
• Oil consumption - Refer to: Oil Consumption Diagnosis
• Vacuum leak @ Engine - Oil Level Indicator and Tube /Oil Filler Cap

• If a condition exists 

  Repair or replace as necessary

• Go to next step: If no condition exists