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Tahoe / Yukon Service Manual

DTC P205B-P205E

Engine Controls and Fuel - 3.0L LM2 Diesel | Diagnostic Information and Procedures | Document ID: 5507533 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 P205B Reductant Tank Temperature Sensor Performance DTC P205C Reductant Tank Temperature Sensor Circuit Low DTC P205D Reductant Tank Temperature Sensor Circuit High DTC P205E Reductant Tank Temperature Sensor Circuit Erratic Diagnostic Fault Information

Circuit Short to Ground Open/High Resistance Short to Voltage Signal Performanc
Signal P205C P205D P131C, P205D P205B, P205E
Low Reference — P205D — P205B, P205E

Typical Scan Tool Data Reductant Tank Temperature Sensor 2

Circuit Short to Ground Open Short to Voltage
Operating Conditions: Engine = Idling Parameter Normal Range: −39 to 79°C (−38 to 174°F)
Signal 80°C (176°F) −40°C (−40°F) −40°C (−40°F)
Low Reference — 80°C (176°F) —

Circuit/System Description For an overview of the component/system, refer to: Exhaust Aftertreatment System Description

Circuit Description
Signal The control module input circuit has an internal resistance connected to 5 V.
Low Reference Grounded through the control module.
Component Description
B214 Reductant Temperature Sensor The sensor is a negative temperature coefficient thermistor. As the temperature of the air, fluid, or metal increases, the resistance of the sensor decreases, varying the voltage on the signal circuit.
K115 Reductant Control Module The control module controls the heating and dosing of the reductant.

Conditions for Running the DTC P205B DTC P10F4, P205C, P205D, P205E, P20FF, U010E, U2412, U2626 = Not set Ignition Off Time = For greater than 8 h Ignition = On Ignition and Start Switch Signal = Greater than 11 V Frequency the DTC runs = Once — Per ignition cycle — After the running conditions are met P205C, P205D DTC P10F4, P20FF = Not set Ignition = On Ignition and Start Switch Signal = Greater than 11 V Frequency the DTC runs = Continuously — After the running conditions are met P205E DTC P10F4, P205C, P205D, P20FF = Not set Ignition = On Ignition and Start Switch Signal = Greater than 11 V Frequency the DTC runs = Continuously — After the running conditions are met Conditions for Setting the DTC P205B Signal circuit = Not within a calibrated range P205C Reductant Temperature = Warmer than 79°C (174°F) P205D Reductant Temperature = Colder than −39°C (−38°F) P205E Signal circuit = Intermittent Actions Taken When the DTC Sets DTCs listed in the DTC Descriptor category = Type A DTC — Additional actions taken: Reductant Injector = Disabled Reductant Tank Heaters = Disabled Reductant Pump = Disabled Driver Information Center Display = Service Exhaust Fluid System 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 the scan tool parameter: Reductant Tank Temperature Sensor 2 = −39 to 79°C (−38 to 174°F) ⇒ If not between −39 and 79°C (−38 and 174°F) Refer to: Circuit/System Testing ⇓ If between −39 and 79°C (−38 and 174°F)
  3. Verify the scan tool parameter: Reductant Tank Temperature Sensor 2 = The value should not spike or drop out. Perform the action while monitoring the parameter: Wiggle the harness and connector: A38 Reductant Pump and Sensor Assembly Wiggle the harness and connector: @ K115 Reductant 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
  4. 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
  5. All OK. Circuit/System Testing
  1. Ignition/Vehicle & All vehicle systems » Off
  2. Disconnect the electrical connector: A38 Reductant Pump and Sensor Assembly
  3. Test for less than 10 Ω between the test points: Low Reference circuit terminal 2 & Ground ⇒ If 10 Ω or greater 3.1. Disconnect the appropriate electrical connector: K115 Reductant Control Module 3.2. Test for less than 2 Ω between the test points: Low Reference circuit terminal 2 @ Component harness & Terminal 18 @ Control module harness ⇒ If 2 Ω or greater » Repair the open/high resistance in the circuit. ⇒ If less than 2 Ω » Replace the component: K115 Reductant Control Module ⇓ If less than 10 Ω
  4. Ignition » On / Vehicle » In Service Mode
  5. Verify the scan tool parameter: Reductant Tank Temperature Sensor 2 = Colder than −39°C (−38°F) ⇒ If −39°C (−38°F) or warmer 5.1. Ignition/Vehicle » Off 5.2. Disconnect the electrical connector: K115 Reductant Control Module 5.3. Test for infinite resistance between the test points: Signal circuit terminal 1 @ 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 ⇓ If colder than −39°C (−38°F)
  6. Connect a 3 A fused jumper wire between the test points: Signal circuit terminal 1 & Low Reference circuit terminal 2
  7. Verify the scan tool parameter: Reductant Tank Temperature Sensor 2 = Warmer than 79°C (174°F) ⇒ If 79°C (174°F) or colder 7.1. Ignition/Vehicle » Off & Remove » Jumper wire(s) 7.2. Disconnect the electrical connector: K115 Reductant Control Module 7.3. Ignition » On / Vehicle » In Service Mode 7.4. Test for less than 1 V between the test points: Signal circuit terminal 1 @ Component harness & Ground ⇒ If 1 V or greater » Repair the short to voltage on the circuit. ⇓ If less than 1 V 7.5. Ignition/Vehicle » Off 7.6. Test for less than 2 Ω between the test points: Signal circuit terminal 1 @ Component harness & Terminal 6 @ Control module harness ⇒ If 2 Ω or greater » Repair the open/high resistance in the circuit. ⇒ If less than 2 Ω » Replace the component: K115 Reductant Control Module ⇓ If warmer than 79°C (174°F)
  8. Replace the component: A38 Reductant Pump and Sensor Assembly Repair Instructions Perform the Diagnostic Repair Verification after completing the repair: Diagnostic Repair Verification Reductant Control Module Replacement — K115 Reductant Control Module Emission Reduction Fluid Tank Replacement — A38 Reductant Pump and Sensor Assembly For control module replacement, programming, and setup refer to: Control Module References Additional Procedures