LEMON Manuals: Even more car manuals for everyone
Home >> Chevrolet >> 2021 >> Blazer RS, FWD >> Repair and Diagnosis >> External Pages >> Different variant/trim >> Section 10 (Engine Controls And Fuel - 2.0L (LSY) - Diagnostic Information And Procedures (1 Of 2)) >> Diagnostic Information and Procedures >> DTC P0231, P0232, or P023F >> Circuit/System Testing

Circuit/System Testing

WARNING: This page is about a different variant/trim than selected.
NOTE:

It may take up to 2 min for all vehicle systems to power down before an accurate ground or low reference circuit continuity test can be performed.

  1. Ignition/Vehicle & All vehicle systems - Off
  2. Disconnect the electrical connector: G12 Fuel Pump
  3. Verify a test lamp turns On between the test points: Low Reference circuit terminal 4 & B+
    • If the test lamp does not turn On 
    1. Disconnect the electrical connector: K111 Fuel Pump Driver Control Module
    2. Test for less than 2 ohms between the test points: Low Reference circuit terminal 4 @ 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: K111 Fuel Pump Driver Control Module
    • Go to next step: If the test lamp turns On 
  4. Connect a test lamp between the test points: Control circuit terminal 3 & Low Reference circuit terminal 4
  5. Ignition - On/Vehicle - In Service Mode
  6. Perform the scan tool control function: Fuel Pump @ K20 Engine Control Module - On and Off

    Verify the test lamp turns On and Off.

    • If the test lamp is always Off 
    1. Ignition/Vehicle - Off & Remove - Test lamp
    2. Disconnect the electrical connector: K111 Fuel Pump Driver Control Module
    3. Test for infinite resistance between the test points: Control 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: Control 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: K111 Fuel Pump Driver Control Module
    • If the test lamp is always On 
    1. Ignition/Vehicle - Off & Remove - Test lamp
    2. Disconnect the electrical connector: K111 Fuel Pump Driver Control Module
    3. Ignition - On/Vehicle - In Service Mode
    4. Test for less than 1 V between the test points: Control 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: K111 Fuel Pump Driver Control Module
    • Go to next step: If the test lamp turns On and Off 
  7. Ignition/Vehicle & All vehicle systems - Off
  8. Disconnect the electrical connector: K111 Fuel Pump Driver Control Module
  9. Connect a DMM, set on the diode setting, between the test points:
    • Red lead @ Low Reference terminal 24
    • Black lead @ Ground terminal 22
  10. Verify the DMM displays between 0.4 and 0.8 V.
    • If not between 0.4 and 0.8 V 

      Replace the component: K111 Fuel Pump Driver Control Module

    • Go to next step: If between 0.4 and 0.8 V 
  11. Connect a DMM, set on the diode setting, between the test points:
    • Red lead @ Ground terminal 22
    • Black lead @ Low Reference terminal 24
  12. Verify the DMM displays the following: O.L.
    • If not the specified value 

      Replace the component: K111 Fuel Pump Driver Control Module

    • Go to next step: If the specified value 
  13. Test or replace the component: G12 Fuel Pump
scientia non olet · About LEMON Manuals