Circuit/System Testing

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Ignition/Vehicle & All vehicle systems - Off
Disconnect the electrical connector: Q44 Engine Oil Pressure Control Solenoid Valve
Ignition - On / Vehicle - In Service Mode
Verify a test lamp turns On between the test points:Ignition circuit terminal 1/A & Ground
- If the test lamp does not turn On and the circuit fuse is OK
1. Ignition/Vehicle - Off & Remove - Test lamp
2. Test for less than 2 Ω between the test points:Ignition circuit terminal 1/A & Output terminal@Fuse
  - If 2 Ω or greater - Repair the open/high resistance in the circuit.
  - If less than 2 Ω - Verify the fuse is OK and there is voltage at the fuse.
- If the test lamp does not turn On and the circuit fuse is open
1. Ignition/Vehicle - Off & Remove - Test lamp
2. Test for infinite resistance between the test points:Ignition circuit terminal 1/A & Ground
  NOTE: The ignition circuit supplies voltage to other components. Test all circuits for a short to ground or test all components for being shorted.
  - If less than infinite resistance - Repair the short to ground on the circuit.
  - If infinite resistance - Replace the component: Q44 Engine Oil Pressure Control Solenoid Valve
- Go to next step: If the test lamp turns On
Verify a test lamp does not turn On between the test points:Control circuit terminal 2/B & B+
- If the test lamp turns On
1. Ignition/Vehicle - Off & Remove - Test lamp
2. Disconnect the electrical connector: K20 Engine Control Module
3. Test for infinite resistance between the test points:Control circuit terminal 2/B @ Component harness & Ground
  - If less than infinite resistance - Repair the short to ground on the circuit.
  - If infinite resistance - Replace the component: K20 Engine Control Module
- Go to next step: If the test lamp does not turn On
Remove - Test Lamp
Perform the scan tool control function: Engine Oil Pressure Control Solenoid Valve - On
Verify the scan tool parameter: Engine Oil Pressure Control Solenoid Valve Control Circuit High Voltage Test Status = OK or Not Run
- If not the specified state
1. Ignition/Vehicle - Off
2. Disconnect the electrical connector: K20 Engine Control Module
3. Ignition - On / Vehicle - In Service Mode
4. Test for less than 1 V between the test points:Control circuit terminal 2/B @ 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 the specified state
Connect a 3 A fused jumper wire between the test points:Control circuit terminal 2/B & Ignition circuit terminal 1/A
Perform the scan tool control function: Engine Oil Pressure Control Solenoid Valve - On
Verify the scan tool parameter: Engine Oil Pressure Control Solenoid Valve Control Circuit High Voltage Test Status = Malfunction
- If not the specified state
1. Ignition/Vehicle - Off & Remove - Jumper wire(s)
2. Disconnect the electrical connector: K20 Engine Control Module
3. Test for less than 2 Ω between the test points:Control circuit terminal 2/B @ Component harness & The other end of the circuit @ Control module harness
  - If 2 Ω or greater - Repair the open/high resistance in the circuit.
  - If less than 2 Ω - Replace the component: K20 Engine Control Module
- Go to next step: If the specified state
Test or replace the component:Q44 Engine Oil Pressure Control Solenoid Valve