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Tahoe / Yukon Service Manual

DTC P2381-P2384

Engine Controls and Fuel - 3.0L LM2 Diesel | Diagnostic Information and Procedures | Document ID: 5507956 Diagnostic Instructions Perform the Diagnostic System Check prior to using this diagnostic procedure: Diagnostic System Check - Vehicle Review the description of Strategy Based Diagnosis: Strategy Based Diagnosis An overview of each diagnostic category can be found here: Diagnostic Procedure Instructions DTC Descriptor DTC P2381 Exhaust Gas Recirculation Pressure Sensor Circuit High DTC P2382 Exhaust Gas Recirculation Pressure Sensor Circuit Low DTC P2383 Exhaust Gas Recirculation Pressure Sensor Performance DTC P2384 Exhaust Gas Recirculation Pressure Sensor Circuit Intermittent Diagnostic Fault Information

Circuit Short to Ground Open/High Resistance Short to Voltage Signal Performanc
5 V Reference P0652 P2382 P0652 P2383
Signal P2382 P2382 P2381 P2383
Low Reference — P2381 — P2383

Typical Scan Tool Data Exhaust Gas Recirculation Pressure Sensor

Circuit Short to Ground Open Short to Voltage
Operating Conditions: Engine = Idling — At normal operating temperature. Parameter Normal Range: 0 to 10 kPa (0 to 1.5 PSI)
5 V Reference 0 kPa (0 PSI) 0 kPa (0 PSI) 72 kPa (10.4 PSI)
Signal 0 kPa (0 PSI) 0 kPa (0 PSI) 0 kPa (0 PSI)
Low Reference — 0 kPa (0 PSI) —

Circuit/System Description For an overview of the component/system, refer to: Exhaust Gas Recirculation (EGR) System Description

Circuit Description
5 V Reference Regulated voltage supplied by the control module.
Signal The control module input circuit has an internal resistance connected to ground.
Low Reference Grounded through the control module.
Component Description
B345R Exhaust Pressure Differential Sensor - Exhaust Gas Recirculation The signal voltage increases when the pressure increases.
K20 Engine Control Module The control module controls a series of actuators to ensure optimal engine performance. The control module does this by reading values from a variety of sensors, interprets the data and adjusts the engine actuators accordingly.

Conditions for Running the DTC P2381, P2382 Ignition = On or Engine = Running Ignition and Start Switch Signal = Greater than 11 V Frequency the DTC runs = Continuously — After the running conditions are met — For greater than 4 s P2383 DTCs related to the following system/component = Not Set – M122 Exhaust Pressure Regulator Valve – Q14B Exhaust Gas Recirculation Valve 2 No other DTCs related to the concerned component are set. Ignition = On or Engine = Running Ignition and Start Switch Signal = Greater than 11 V Frequency the DTC runs = Continuously — After the running conditions are met P2384 Ignition = On or Engine = Running Ignition and Start Switch Signal = Greater than 11 V No other DTCs related to the concerned component are set. Frequency the DTC runs = Continuously — After the running conditions are met — For greater than 4 s Conditions for Setting the DTC P2381 Signal circuit = Short to Voltage P2382 Signal circuit = Short to Ground P2383, P2384 Signal circuit = Not within a calibrated range Actions Taken When the DTC Sets DTCs listed in the DTC Descriptor category = Type A DTC Conditions for Clearing the DTC DTCs listed in the DTC Descriptor category = Type A DTC Reference Information Schematic Reference Engine Controls Schematics Connector End View Reference Master Electrical Component List Electrical Information Reference Circuit Testing Connector Repairs Testing for Intermittent Conditions and Poor Connections Wiring Repairs DTC Type Reference Powertrain Diagnostic Trouble Code (DTC) Type Definitions Scan Tool Reference Control Module References Circuit/System Verification

  1. Ignition » On / Vehicle » In Service Mode
  2. Verify DTC P0652 is not set. ⇒ If the DTC is set Refer to: DTC P0641, P0651, P0697, or P06A3 ⇓ If the DTC is not set
  3. Verify the scan tool parameter: Exhaust Gas Recirculation Pressure Sensor = 0 to 10 kPa (0 to 1.5 PSI) ⇒ If not between 0 and 10 kPa (0 and 1.5 PSI) Refer to: Circuit/System Testing ⇓ If between 0 and 10 kPa (0 and 1.5 PSI)
  4. Verify the scan tool parameter: Exhaust Gas Recirculation Pressure Sensor = The value should not spike or drop out. Perform the action while monitoring the parameter: Wiggle the harness and connector: B345R Exhaust Pressure Differential Sensor - Exhaust Gas Recirculation Wiggle the harness and connector: X1 @ K20 Engine Control Module ⇒ If the value spikes or drops out Repair as necessary » Wiring / Terminal(s) / Electrical Connector(s) ⇓ If the value does not spike or drop out
  5. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data. Verify the DTC does not set. ⇒ If the DTC sets Refer to: Circuit/System Testing ⇓ If the DTC is not set
  6. All OK. Circuit/System Testing
  1. Ignition/Vehicle & All vehicle systems » Off
  2. Disconnect the electrical connector: B345R Exhaust Pressure Differential Sensor - Exhaust Gas Recirculation
  3. Test for less than 10 Ω between the test points: Low Reference circuit terminal 3 & Ground ⇒ If 10 Ω or greater 3.1. Disconnect the electrical connector: X1 @ K20 Engine Control Module 3.2. Test for less than 2 Ω between the test points: Low Reference circuit terminal 3 @ Component harness & Terminal 19 X1 @ 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 ⇓ If less than 10 Ω
  4. Ignition » On / Vehicle » In Service Mode
  5. Test for 4.8 to 5.2 V between the test points: 5 V Reference circuit terminal 1 & Low Reference circuit terminal 3 ⇒ If less than 4.8 V 5.1. Ignition/Vehicle » Off 5.2. Disconnect the electrical connector: X1 @ K20 Engine Control Module 5.3. Test for infinite resistance between the test points: 5 V Reference circuit terminal 1 @ Component harness & Ground ⇒ If less than infinite resistance » Repair the short to ground on the circuit. ⇓ If infinite resistance 5.4. Test for less than 2 Ω between the test points: 5 V Reference circuit terminal 1 @ Component harness & Terminal 48 X1 @ 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 ⇒ If greater than 5.2 V 5.1. Ignition/Vehicle » Off 5.2. Disconnect the electrical connector: X1 @ K20 Engine Control Module 5.3. Ignition » On / Vehicle » In Service Mode 5.4. Test for less than 1 V between the test points: 5 V Reference 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 ⇓ If between 4.8 and 5.2 V
  6. Verify the scan tool parameter: Exhaust Gas Recirculation Pressure Sensor = Less than 0.5 V ⇒ If 0.5 V or greater 6.1. Ignition/Vehicle » Off 6.2. Disconnect the electrical connector: X1 @ K20 Engine Control Module 6.3. 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 ⇓ If less than 0.5 V
  7. Connect a 3 A fused jumper wire between the test points: Signal circuit terminal 2 & 5 V Reference circuit terminal 1
  8. Verify the scan tool parameter: Exhaust Gas Recirculation Pressure Sensor = Greater than 4.8 V ⇒ If 4.8 V or less 8.1. Ignition/Vehicle » Off & Remove » Jumper wire(s) 8.2. Disconnect the electrical connector: X1 @ K20 Engine Control Module 8.3. 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. ⇓ If infinite resistance 8.4. Ignition/Vehicle » Off 8.5. Test for less than 2 Ω between the test points: Signal circuit terminal 2 @ Component harness & Terminal 84 X1 @ 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 ⇓ If greater than 4.8 V
  9. Replace the component: B345R Exhaust Pressure Differential Sensor - Exhaust Gas Recirculation Repair Instructions Perform the Diagnostic Repair Verification after completing the repair: Diagnostic Repair Verification Exhaust Pressure Sensor Pipe Replacement - Exhaust Gas Recirculation Cooler — B345R  Exhaust Pressure Differential Sensor - Exhaust Gas Recirculation For control module replacement, programming, and setup refer to: Control Module References