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Tahoe / Yukon Service Manual

DTC P1018, P1019, P131B,

Engine Controls and Fuel - 3.0L LM2 Diesel | Diagnostic Information and Procedures | Document ID: 5471892 DTC P1018, P1019, P131B, P131C, P203B-P203D, P206B- P206D, P21C5, P2ADA-P2ADD, U2627, U2628, or U2630 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 P1018 Reductant Control Module Sensor Reference Circuit Low DTC P1019 Reductant Control Module Sensor Reference Circuit High DTC P131B Reductant Control Module Sensor Reference 3 Circuit Low DTC P131C Reductant Control Module Sensor Reference 3 Circuit High DTC P203B Reductant Level Sensor Performance DTC P203C Reductant Level Sensor Circuit Low DTC P203D Reductant Level Sensor Circuit High DTC P206B Reductant Quality Sensor Circuit Performance DTC P206C Reductant Quality Sensor Circuit Low DTC P206D Reductant Quality Sensor Circuit High DTC P21C5 Reductant Level Sensor Stuck DTC P2ADA Reductant Tank Temperature Sensor 2 Circuit Performance DTC P2ADB Reductant Tank Temperature Sensor 2 Circuit Low DTC P2ADC Reductant Tank Temperature Sensor 2 Circuit High DTC P2ADD Reductant Tank Temperature Sensor 2 Circuit Erratic DTC U2627 Reductant Control Module Lost Communication with Reductant Level Sensor DTC U2628 Reductant Control Module Lost Communication with Reductant Concentration Sensor DTC U2630 Reductant Control Module Lost Communication with Reductant Tank Temperature Sensor 2 Circuit/System Description The reductant quality sensor includes an integrated level sensor and temperature sensor to measure reductant fluid level and temperature. The reductant quality sensor is located in the reductant tank and uses an ultrasonic signal to measure reductant fluid quality and level. The reductant quality sensor communicates with the reductant control module using serial data. Conditions for Running the DTC P1018, P1019, P131B, P131C, P203C, P203D, P206C, P206D, P2ADB, P2ADC, P2ADD DTC P10F4, P20FF, U2627, U2627, U2630 = Not set No other DTCs related to the concerned component are set. Ignition = On Ignition Voltage = Greater than 11 V Frequency the DTC runs = Continuously — After the running conditions are met — For greater than 4 s P203B, P206B DTC U2627, U2628, U2630 = Not set No other DTCs related to the concerned component are set. Ignition = On Ignition Voltage = Greater than 11 V Reductant Level — Calculated = Greater than 5 L (1.3 US Liquid Gal) Reductant Tank Heaters = Off Reductant Temperature = Greater than 0°C (32°F) Vehicle Speed = Less than 2 km/h (1.2 MPH) Frequency the DTC runs = Continuously — After the running conditions are met — For greater than 200 s P21C5 DTC P10C6, P10F4, P20FF, P21CB, U2412, U2626, U2627, U2628, U2630 = Not set No other DTCs related to the concerned component are set. Ignition = On Ignition Voltage = Greater than 11 V Reductant Level — Calculated = Greater than 5 L (1.3 US Liquid Gal) Reductant Temperature = Greater than 0°C (32°F) Vehicle Speed = Greater than 25 km/h (15.5 MPH) Frequency the DTC runs = Continuously — After the running conditions are met — For greater than 20 s P2ADA DTC P10F4, P20FF, U2627, U2628, U2630 = Not set No other DTCs related to the concerned component are set. Ignition = Off — For greater than 8 h Ignition = On Ignition Voltage = Greater than 11 V Frequency the DTC runs = Continuously — After the running conditions are met — For greater than 3 s U2627, U2628, U2630 DTC P10F4, P20FF = Not set Ignition = On Ignition Voltage = Greater than 11 V Frequency the DTC runs = Continuously — After the running conditions are met Conditions for Setting the DTC P1018, P1019, P131B, P132C Reductant Sensor Module Supply Voltage = Not within a calibrated range P203B, P203C, P203D, P21C5, U2627 Reductant Level Sensor = Not within a calibrated range P206B, P206C, P206D, U2628 Reductant Quality Sensor = Not within a calibrated range P2ADA, P2ADB, P2ADC, P2ADD, U2630 Reductant Temperature Sensor 2= Not within a calibrated range Actions Taken When the DTC Sets DTCs listed in the DTC Descriptor category = Type A DTC — Exceptions listed below DTC P203B, P203C, P203D, P21C5 = Type B DTC The control module uses default replacement values. Warning Message = Service Emission System or Service Exhaust Fluid System Conditions for Clearing the DTC DTCs listed in the DTC Descriptor category = Type A DTC — Exceptions listed below DTC P203B, P203C, P203D, P21C5 = Type B 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. Verify DTC P1018, P1019, P131B, P131C, P203B, P203C, P203D, P206B, P206C, P206D, P21C5, P2ADA, P2ADB, P2ADC, P2ADD, U2627, U2628, U2630 is not set. ⇒ If any of the DTCs are set Refer to Circuit/System Testing ⇓ If none of the DTC are set
  2. 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.
  3. Verify that DTCs P1018, P1019, P131B, P131C, P203B, P203C, P203D, P206B, P206C, P206D, P21C5, P2ADA, P2ADB, P2ADC, P2ADD, U2627, U2628, or U2630 are not set. ⇒ If any of the DTCs are set Refer to Circuit/System Testing ⇓ If no DTC Is set
  4. All OK. Circuit/System Testing
  1. Ignition Off, disconnect the harness connector at the B212 Reductant Sensor Module .
  2. Test for less than 10 Ω between low reference terminal 3 and ground. ⇒ If greater than 10 Ω 2.1. Ignition Off, disconnect the harness connector at the K115 Reductant Control Module. 2.2. Test for less than 2 Ω between low reference terminal 3 at the component harness and terminal 9 at the control module harness. ⇒ If 2 Ω or greater, repair the open/high resistance in the circuit. ⇒ If less than 2 Ω, replace the K115 Reductant Control Module. ⇓ If less than 10 Ω
  3. Ignition » On / Vehicle » In Service Mode
  4. Test for 4.6 to 5.4 V between 5 V reference circuit terminal 1 and ground ⇒ If less than 4.6 V 4.1. Ignition Off, disconnect the harness connector at the K115 Reductant Control Module. 4.2. Test for less than 2 Ω between 5 V reference terminal 1 at the component harness and terminal 7 at the control module harness. ⇒ If 2 Ω or greater, repair the open/high resistance in the circuit. ⇓ If less than 2 Ω 4.3. Test for infinite resistance between the 5 V reference terminal 1 at the component harness and ground. ⇒ If less than infinite resistance, repair the short to ground on the circuit. ⇒ If infinite resistance, replace the K115 Reductant Control Module ⇒ If greater than 5.4 V 4.1. Ignition Off, disconnect the harness connector at the K115 Reductant Control Module. 4.2. Ignition » On / Vehicle » In Service Mode 4.3. Test for less than 1 V between the 5 V reference terminal 1 at the component harness and ground. ⇒ If 1 V or greater, repair the short to voltage in the circuit. ⇒ If less than 1 V, replace the K115 Reductant Control Module ⇓ If between 4.6 and 5.4 V
  5. Ignition » On / Vehicle » In Service Mode
  6. Test for 4.8 to 5.2 V between serial data circuit terminal 2 and ground. ⇒ If less than 4.8 V 6.1. Ignition Off, disconnect the harness connector at the K115 Reductant Control Module. 6.2. Test for less than 2 Ω in between serial data circuit terminal 2 at the component harness and terminal 8 at the control module harness. ⇒ If 2 Ω or greater, repair the open/high resistance in the circuit. ⇓ If less than 2 Ω 6.3. Test for infinite resistance between the serial data circuit terminal 2 at the component harness and ground. ⇒ If less than infinite resistance, repair the short to ground on the circuit. ⇒ If infinite resistance, replace the K115 Reductant Control Module ⇒ If greater than 4.8 V 6.1. Ignition Off, disconnect the harness connector at the K115 Reductant Control Module. 6.2. Ignition » On / Vehicle » In Service Mode 6.3. Test for less than 1 V between the serial data circuit terminal 2 at the component harness and ground. ⇒ If 1 V or greater, repair the short to voltage in the circuit. ⇒ If less than 1 V, replace the K115 Reductant Control Module ⇓ If between 4.4 and 4.8 V
  7. Replace the component: B212 Reductant Sensor Module . Repair Instructions Perform the Diagnostic Repair Verification after completing the repair: Diagnostic Repair Verification Emission Reduction Fluid Tank Replacement — B212 Reductant Sensor Module Reductant Control Module Replacement — K115 Reductant Control Module