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Tahoe / Yukon Service Manual

DTC P118F or P1196

Engine Controls and Fuel - 3.0L LM2 Diesel | Diagnostic Information and Procedures | Document ID: 5504056 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 P118F Exhaust Gas Temperature Sensor 2 Performance - Engine Running DTC P1196 Exhaust Gas Temperature Sensor 3 Performance - Engine Running Diagnostic Fault Information

Circuit Short to Ground Open/High Resistance Short to Voltage Signal Performanc
Signal P2032, P242C P2033, P242D P2033, P242D P118F, P1196*
Low Reference — P2032, P242C — P118F, P1196*
* Additional DTCs may set

Typical Scan Tool Data Exhaust Gas Temperature Sensor 2,3

Circuit Short to Ground Open Short to Voltage
Operating Conditions: Engine = Idling Parameter Normal Range: −39 to 999°C (−38 to 1830°F)
Signal 1,000°C (1,832°F) −40°C (−40°F) −40°C (−40°F)
Low Reference — 1,000°C (1,832°F) −40°C (−40°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 2.4 V.
Low Reference The control module input circuit has an internal resistance connected to 1 V.
Component Description
B131 Exhaust Temperature Sensor The temperature sensor is a negative temperature coefficient thermistor, a resistor which changes based on temperature.
K20 Engine Control Module The control module contains a microprocessor used to process input data to control outputs. 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 P118F DTC P262B, U029D = Not set DTCs related to the following system/component = Not Set – B17 Barometric Pressure Sensor – B34 Engine Coolant Temperature Sensor – B66 Intake Air Temperature Sensor – B74 Manifold Absolute Pressure Sensor – B75C Multifunction Intake Air Sensor – B115 Vehicle Speed Sensor – B131A Exhaust Temperature Sensor 1 – B131C Exhaust Temperature Sensor 3 – B154 Diesel Particulate Filter Exhaust Differential Pressure Sensor – B195A Nitrogen Oxides Sensor 1 – Q14 Exhaust Gas Recirculation Valve – Q17 Fuel Injector No other DTCs related to the concerned component are set. Engine Run Time = For greater than 2 min Ignition and Start Switch Signal = Greater than 11 V Frequency the DTC runs = Continuously — After the running conditions are met — For greater than 8 s P1196 DTCs related to the following system/component = Not Set – B9 Ambient Air Temperature Sensor – B17 Barometric Pressure Sensor – B34 Engine Coolant Temperature Sensor – B66 Intake Air Temperature Sensor – B74 Manifold Absolute Pressure Sensor – B75C Multifunction Intake Air Sensor – B115 Vehicle Speed Sensor – Q14 Exhaust Gas Recirculation Valve – Q17 Fuel Injector No other DTCs related to the concerned component are set. Engine Run Time = For greater than 2 min Ignition and Start Switch Signal = Greater than 11 V Frequency the DTC runs = Continuously — After the running conditions are met — For greater than 8 s Conditions for Setting the DTC Exhaust Temperature Sensor = Not within a calibrated range Actions Taken When the DTC Sets DTCs listed in the DTC Descriptor category = Type B DTC Conditions for Clearing the DTC DTCs listed in the DTC Descriptor category = Type B DTC Diagnostic Aids After starting a cold engine, the following scan tool parameter value should rise steadily and then stabilize: Exhaust Gas Temperature Sensor 2,3 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: Exhaust Gas Temperature Sensor 2, 3 = −39 to 999°C (−38 to 1,830°F) ⇒ If not between −39 and 999°C (−38 and 1,830°F) Refer to: Circuit/System Testing ⇓ If between −39 and 999°C (−38 and 1,830°F)
  3. Verify the scan tool parameter: Exhaust Gas Temperature Sensor 2, 3 = The value should not spike or drop out. Perform the action while monitoring the parameter: Wiggle the harness and connector: Exhaust Gas Temperature Sensor 2, 3 Wiggle the harness and connector: X2 @ 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
  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
  6. Ignition/Vehicle & All vehicle systems » Off
  7. Disconnect the appropriate electrical connector: B131 Exhaust Temperature Sensor
  8. Ignition » On / Vehicle » In Service Mode
  9. Test for 0.5 to 1.5 V between the test points: Terminal 2 & Ground ⇒ If greater than 1.5 V 4.1. Ignition/Vehicle » Off 4.2. Disconnect the electrical connector: K20 Engine Control Module 4.3. Test for less than 1 V between the test points: 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 4.1. Ignition/Vehicle » Off 4.2. Disconnect the electrical connector: K20 Engine Control Module 4.3. Test for infinite resistance between the test points: Terminal 2 @ Component harness & Ground ⇒ If less than infinite resistance » Repair the short to ground on the circuit. ⇓ If infinite resistance 4.4. Test for less than 2 Ω between the test points: { Sensor 2 } Terminal 2 @ Component harness & The other end of the circuit @ Control module harness { Sensor 3 } Terminal 2 @ Component harness & The other end of the circuit @ 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 between 0.5 and 1.5 V
  10. Ignition » On / Vehicle » In Service Mode
  11. Verify the scan tool parameter: Exhaust Gas Temperature Sensor 2,3 = Colder than −39°C (−38°F) ⇒ If warmer than −39°C (−38°F) 6.1. Ignition/Vehicle » Off 6.2. Disconnect the electrical connector: K20 Engine Control Module 6.3. 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: K20 Engine Control Module ⇓ If colder than −39°C (−38°F)
  12. Connect a 3 A fused jumper wire between the test points: Signal circuit terminal 1 & Ground
  13. Verify the scan tool parameter: Exhaust Gas Temperature Sensor 2,3 = Warmer than 999°C (1,830°F) ⇒ If colder than 999°C (1,830°F) 8.1. Ignition/Vehicle » Off & Remove » Jumper wire(s) 8.2. Disconnect the electrical connector: K20 Engine Control Module 8.3. Ignition » On / Vehicle » In Service Mode 8.4. 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 8.5. Ignition/Vehicle » Off 8.6. Test for less than 2 Ω between the test points: { Sensor 2 } Signal circuit terminal 1 @ Component harness & The other end of the circuit @ Control module harness { Sensor 3 } Signal circuit terminal 1 @ Component harness & The other end of the circuit @ 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 warmer than 999°C (1,830°F)
  14. Test or replace the component: B131 Exhaust Temperature Sensor Component Testing
  15. Ignition/Vehicle » Off
  16. Disconnect the appropriate electrical connector: B131 Exhaust Temperature Sensor
  17. Test the resistance between the test points: Terminal 1 & Terminal 2
  18. Verify the value is within the range listed in the table: Temperature Versus Resistance ⇒ If not in the specified range Replace the component: B131 Exhaust Temperature Sensor ⇓ If in the specified range
  19. Test for infinite resistance between the test points: Each terminal of the component & The component’s housing ⇒ If less than infinite resistance Replace the component: B131 Exhaust Temperature Sensor ⇓ If infinite resistance
  20. All OK. Repair Instructions Perform the Diagnostic Repair Verification after completing the repair: Diagnostic Repair Verification Exhaust Gas Temperature Sensor Replacement - Position 2 Exhaust Gas Temperature Sensor Replacement - Position 3 For control module replacement, programming, and setup refer to: Control Module References