LEMON Manuals: Even more car manuals for everyone
Home >> Chevrolet >> 2020 >> Express 2500 LS, 6.0L Eng VIN G >> Repair and Diagnosis >> External Pages >> Different car >> Section 94 (Engine Controls And Fuel - 2.8L (LWN) Diesel - Diagnostic Information And Procedures (3 Of 3)) >> Diagnostic Information and Procedures >> DTC P205B-P205D >> Circuit/System Testing

Circuit/System Testing

WARNING: This page is about a different car, the 2019 GMC Savana 3500, 2019 GMC Savana 2500, 2019 Chevrolet Express 3500, and 2019 Chevrolet Express 2500. However, it is still accessible from the selected car via links, so may be relevant.
    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: A38 Reductant Pump and Sensor Assembly
  3. Test for less than 10 ohms between the test points: Low Reference circuit terminal 2/B & Ground
    • If 10 ohms or greater 
    1. Disconnect the appropriate electrical connector: K115 Reductant Control Module
    2. Test for less than 2 ohms between the test points: Low Reference circuit terminal 2/B @ 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: K115 Reductant Control Module
    • Go to next step: If less than 10 ohms 
  4. Ignition - On / Vehicle - In Service Mode
  5. Verify the scan tool parameter: Reductant Temperature = Colder than -39°C (-38°F)
    • If warmer than -39°C (-38°F) 
    1. Ignition/Vehicle - Off
    2. Disconnect the appropriate electrical connector: K115 Reductant Control Module
    3. Test for infinite resistance between the test points: Signal circuit terminal 1/A @ Component harness & Ground
      • If less than infinite resistance - Repair the short to ground on the circuit.
      • If infinite resistance - Replace the component: K115 Reductant Control Module
    • Go to next step: If colder than -39°C (-38°F) 
  6. Connect a 3 A fused jumper wire between the test points: Signal circuit terminal 1/A & Low Reference circuit terminal 2/B
  7. Verify the scan tool parameter: Reductant Temperature = Warmer than 75°C (164°F)
    • If 75°C (164°F) or colder 
    1. Ignition/Vehicle - Off & Remove - Jumper wire(s)
    2. Disconnect the appropriate electrical connector: K115 Reductant Control Module
    3. Ignition - On / Vehicle - In Service Mode
    4. Test for less than 1 V between the test points: Signal circuit terminal 1/A @ Component harness & Ground
      • If 1 V or greater - Repair the short to voltage on the circuit.
      • Go to next step: If less than 1 V
    5. Ignition/Vehicle - Off
    6. Test for less than 2 ohms between the test points: Signal circuit terminal 1/A @ 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: K115 Reductant Control Module
    • Go to next step: If warmer than 75°C (164°F) 
  8. Test or replace the component: A38 Reductant Pump and Sensor Assembly
scientia non olet · About LEMON Manuals