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Engine Controls - 8.1L - Diagnostics (Dtcs P0030-P0174): Overview Chevrolet Silverado 1500

Test Description

The number below refers to the step number on the diagnostic table.

  1. 7: With no fault present, the test lamp will blink once per second.
StepActionValue(s)YesNo
Schematic Reference: Engine Controls Schematics Connector End View Reference: Powertrain Control Module (PCM) Connector End Views or Engine Controls Connector End Views
1Did you perform the Diagnostic System Check - Vehicle?Go to Step 2Go to Diagnostic System Check - Vehicle
2IMPORTANT: Whenever the heated oxygen sensor (HO2S) heaters are commanded ON with a scan tool, they will continue to be pulsed ON once per second until the ignition is turned OFF for 30 seconds. Turn ON the ignition, with the engine OFF. Command the HO2S heaters ON with a scan tool. Wait 15 seconds to allow the HO2S heater current to stabilize. Observe the affected HO2S Heater Current parameter with a scan tool. Is the HO2S Heater Current parameter within the specified range?0.25-3.125 AGo to Step 3Go to Step 4
3Observe the Freeze Frame/Failure Records for this DTC. Turn OFF the ignition for 30 seconds. Start the engine. 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. Did the DTC fail this ignition?Go to Step 4Go to Testing for Intermittent Conditions and Poor Connections
4Inspect the O2A or O2B fuse. Is the O2A or O2B fuse open?Go to Step 5Go to Step 6
5Test the ignition 1 voltage circuit for a short to ground. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition?Go to Step 20Go to Step 8
6Disconnect the affected HO2S. Turn ON the ignition, with the engine OFF. Probe the ignition 1 voltage circuit of the HO2S harness connector on the engine harness side with a test lamp that is connected to a good ground. Refer to Probing Electrical Connectors . Does the test lamp illuminate?Go to Step 7Go to Step 17
7IMPORTANT: The test lamp may blink prior to commanding the heaters ON. This is because the heaters were commanded ON in a previous step. To command the heaters OFF, turn OFF the ignition for 30 seconds. Connect a test lamp between the ignition 1 voltage circuit of the HO2S harness connector on the engine harness side and the HO2S heater low control circuit of the HO2S harness connector on the engine harness side. Command the HO2S heaters ON with a scan tool. Does the test lamp blink once per second?Go to Step 9Go to Step 10
8IMPORTANT: Perform the following test on all HO2S which are supplied voltage by the suspect circuit. Test the ignition 1 voltage circuit on the sensor side of the HO2S connector for a short to ground. Refer to Circuit Testing .Is any sensor shorted to ground?Go to Step 18Go to Testing for Intermittent Conditions and Poor Connections
9Measure the resistance of the following circuits with a DMM: The HO2S heater low control circuit The ignition 1 voltage circuit Refer to Circuit Testing . Is the resistance of either circuit more than the specified value?3 ohmGo to Step 16Go to Step 14
10Is the test lamp on steady?Go to Step 11Go to Step 12
11Test the HO2S heater low control circuit for a short to ground. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition?Go to Step 20Go to Step 15
12Test the HO2S heater low control circuit for a short to voltage. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition?Go to Step 20Go to Step 13
13Test the HO2S heater low control circuit for an open or high resistance. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition?Go to Step 20Go to Step 15
14Test for shorted terminals and for poor connections at the HO2S. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition?Go to Step 20Go to Step 18
15Test for shorted terminals and for poor connections at the powertrain control module (PCM). Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition?Go to Step 20Go to Step 19
16Repair the circuit with high resistance. Refer to Wiring Repairs . Did you complete the repair?Go to Step 20
17Repair the open or high resistance in the ignition 1 voltage circuit. Refer to Wiring Repairs . Did you complete the repair?Go to Step 20
18Replace the affected HO2S. Refer to the following: Heated Oxygen Sensor (HO2S) Replacement Bank 1 Sensor 1 Heated Oxygen Sensor (HO2S) Replacement Bank 2 Sensor 1 Heated Oxygen Sensor (HO2S) Replacement Bank 1 Sensor 2 Heated Oxygen Sensor (HO2S) Replacement Bank 2 Sensor 2 Did you complete the replacement?Go to Step 20
19Replace the PCM. Refer to Control Module References for replacement, setup, and programming. Did you complete the replacement?Go to Step 20
20Replace the O2A or O2B fuse, if necessary. Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. 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. Did the DTC fail this ignition?Go to Step 2Go to Step 21
21Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed?Go to Diagnostic Trouble Code (DTC) List - VehicleSystem OK
IMPORTANT
Whenever the heated oxygen sensor (HO2S) heaters are commanded ON with a scan tool, they will continue to be pulsed ON once per second until the ignition is turned OFF for 30 seconds.
IMPORTANT
The test lamp may blink prior to commanding the heaters ON. This is because the heaters were commanded ON in a previous step. To command the heaters OFF, turn OFF the ignition for 30 seconds.
IMPORTANT
Perform the following test on all HO2S which are supplied voltage by the suspect circuit.

DTC P0030, P0036, P0050, or P0056

The number below refers to the step number on the diagnostic table.

  1. 9: With no fault present, the test lamp will blink once per second.
StepActionValue(s)YesNo
Schematic Reference: Engine Controls Schematics Connector End View Reference: Engine Controls Connector End Views or Powertrain Control Module (PCM) Connector End Views
1Did you perform the Diagnostic System Check - Vehicle?Go to Step 2Go to Diagnostic System Check - Vehicle
2IMPORTANT: Whenever the heated oxygen sensor (HO2S) heaters are commanded ON with a scan tool, they will continue to be pulsed ON once per second until the ignition is turned OFF for 30 seconds. Turn ON the ignition, with the engine OFF. Command the HO2S heaters ON with a scan tool. Wait 15 seconds to allow the HO2S heater current to stabilize. Observe the affected HO2S heater current parameter with a scan tool. Is the HO2S heater current parameter within the specified range?0.25-3.125 AGo to Step 3Go to Step 4
3Observe the Freeze Frame/Failure Records for this DTC. Turn OFF the ignition for 30 seconds. Start the engine. 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. Did the DTC fail this ignition?Go to Step 4Go to Testing for Intermittent Conditions and Poor Connections
4Inspect the O2A or O2B fuse. Is the O2A or O2B fuse open?Go to Step 5Go to Step 6
5Test the ignition 1 voltage circuit for a short to ground. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition?Go to Step 20Go to Step 8
6Disconnect the affected HO2S. Turn ON the ignition, with the engine OFF. Probe the ignition 1 voltage circuit of the HO2S harness connector on the engine harness side with a test lamp that is connected to a good ground. Refer to Probing Electrical Connectors . Does the test lamp illuminate?Go to Step 7Go to Step 17
7IMPORTANT: The test lamp may blink prior to commanding the heaters ON. This is because the heaters were commanded ON in a previous step. To command the heaters OFF, turn OFF the ignition for 30 seconds. Connect a test lamp between the ignition 1 voltage circuit of the HO2S harness connector on the engine harness side and the HO2S heater low control circuit of the HO2S harness connector on the engine harness side. Command the HO2S heaters ON with a scan tool. Does the test lamp blink once per second?Go to Step 9Go to Step 10
8IMPORTANT: Perform the following test on all HO2S' which are supplied voltage by the suspect circuit. Test the ignition 1 voltage circuit on the sensor side of the HO2S connector for a short to ground. Refer to Circuit Testing .Is any sensor shorted to ground?Go to Step 18Go to Testing for Intermittent Conditions and Poor Connections
9Measure the resistance of the following circuits with a DMM: The HO2S heater low control circuit The ignition 1 voltage circuit Refer to Circuit Testing . Is the resistance of either circuit more than the specified value?3 ohmGo to Step 16Go to Step 14
10Is the test lamp on steady?Go to Step 11Go to Step 12
11Test the HO2S heater low control circuit for a short to ground. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition?Go to Step 20Go to Step 15
12Test the HO2S heater low control circuit for a short to voltage. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition?Go to Step 20Go to Step 13
13Test the HO2S heater low control circuit for an open or high resistance. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition?Go to Step 20Go to Step 15
14Test for shorted terminals and for poor connections at the HO2S. Refer to the following procedures: Testing for Intermittent Conditions and Poor Connections Connector Repairs Heated Oxygen Sensor (HO2S) Wiring Repairs Did you find and correct the condition?Go to Step 20Go to Step 18
15Test for shorted terminals and for poor connections at the powertrain control module (PCM). Refer to the following procedures: Testing for Intermittent Conditions and Poor Connections Connector Repairs Heated Oxygen Sensor (HO2S) Wiring Repairs Did you find and correct the condition?Go to Step 20Go to Step 19
16Repair the circuit with high resistance. Refer to Wiring Repairs . Did you complete the repair?Go to Step 20
17Repair the open or high resistance in the ignition 1 voltage circuit. Refer to Wiring Repairs . Did you complete the repair?Go to Step 20
18Replace the affected HO2S. Refer to the following: Heated Oxygen Sensor (HO2S) Replacement Bank 1 Sensor 1 Heated Oxygen Sensor (HO2S) Replacement Bank 1 Sensor 2 Heated Oxygen Sensor (HO2S) Replacement Bank 2 Sensor 1 Heated Oxygen Sensor (HO2S) Replacement Bank 2 Sensor 2 Did you complete the replacement?Go to Step 20
19Replace the PCM. Refer to Control Module References for replacement, setup, and programming. Did you complete the replacement?Go to Step 20
20Replace the O2A or O2B fuse, if necessary. Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. 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. Did the DTC fail this ignition?Go to Step 2Go to Step 21
21Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed?Go to Diagnostic Trouble Code (DTC) List - VehicleSystem OK
IMPORTANT
Whenever the heated oxygen sensor (HO2S) heaters are commanded ON with a scan tool, they will continue to be pulsed ON once per second until the ignition is turned OFF for 30 seconds.
IMPORTANT
The test lamp may blink prior to commanding the heaters ON. This is because the heaters were commanded ON in a previous step. To command the heaters OFF, turn OFF the ignition for 30 seconds.
IMPORTANT
Perform the following test on all HO2S' which are supplied voltage by the suspect circuit.

DTC P0053, P0054, P0059, or P0060

The number below refers to the step number on the diagnostic table.

  1. 5: Locating and repairing an individual condition may correct more than one DTC.
StepActionYesNo
Schematic Reference: Engine Controls Schematics Connector End View Reference: Powertrain Control Module (PCM) Connector End Views or Engine Controls Connector End Views
1Did you perform the Diagnostic System Check - Vehicle?Go to Step 2Go to Diagnostic System Check - Vehicle
2Is DTC P0101, P0102, P0103, P0107, P0108, P0112, P0113, P1111, or P1112 set?Go to Diagnostic Trouble Code (DTC) List - VehicleGo to Step 3
3IMPORTANT: If any of the conditions listed below exist, replace the throttle body assembly. Refer to Throttle Body Assembly Replacement . Inspect the throttle body for the following: Loose or damaged throttle blade Cracked or bent throttle shaft Did you find and correct the condition?Go to Step 4Go to Diagnostic Aids
4Use the scan tool in order to clear the DTCs. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text. Does the DTC run and pass?Go to Step 5Go to Step 2
5With a scan tool, observe the stored information, Capture Info. Does the scan tool display any DTCs that you have not diagnosed?Go to Diagnostic Trouble Code (DTC) List - VehicleSystem OK
IMPORTANT
If any of the conditions listed below exist, replace the throttle body assembly. Refer to Throttle Body Assembly Replacement .

DTC P0068

The numbers below refer to the step numbers on the diagnostic table.

  1. 5: This step will determine if the MAP sensor pressure is within the proper range for a given altitude.
  2. 6: This step will determine if the MAP sensor voltage is within the proper range at idle.
  3. 7: This step will determine if the MAP sensor responds properly to the change in manifold pressure.
  4. 8: This step will determine if the TP sensors are operating properly.
  5. 9: This step will determine if any mechanical faults have caused this DTC to set.
  6. 10: This voltage drop test will determine if high resistance has caused this DTC to set.
StepActionValuesYesNo
Schematic Reference: Engine Controls Schematics Connector End View Reference: Powertrain Control Module (PCM) Connector End Views or Engine Controls Connector End Views
1Did you perform the Diagnostic System Check - Vehicle?Go to Step 2Go to Diagnostic System Check - Vehicle
2Observe the Diagnostic Trouble Code (DTC) Information with the scan tool. Does the scan tool display any other DTCs set?Go to Diagnostic Trouble Code (DTC) List - VehicleGo to Step 3
3Attempt to start the engine. Does the engine start?Go to Step 4Go to Step 5
4Observe the Freeze Frame/Failure Records for this DTC. Turn OFF the ignition for 30 seconds. Start the engine. 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. Did the DTC fail this ignition?Go to Step 5Go to Diagnostic Aids
5IMPORTANT: The Altitude vs. Barometric Pressure table indicates a pressure range for a given altitude under normal weather conditions. Weather conditions consisting of very low or very high pressure and/or temperature may cause a reading to be slightly out of range. Turn ON the ignition, with the engine OFF. Observe the Manifold Absolute Pressure (MAP) Sensor kPa parameter with a scan tool. The MAP sensor pressure should be within the specified range for your altitude. Refer to Altitude vs Barometric Pressure . Is the MAP sensor pressure within the specified range as indicated on the Altitude vs. Barometric Pressure table?Go to Step 6Go to DTC P0106
6Observe the MAP sensor parameter with a scan tool. Start the engine. Does the MAP Sensor parameter decrease?Go to Step 7Go to DTC P0106
7Idle the engine. Observe the MAP Sensor parameter with a scan tool. Increase the engine speed slowly to 3,000 RPM and then back to idle. Does the MAP Sensor parameter change smoothly and gradually through the specified range of the test?Go to Step 8Go to DTC P0106
8Turn OFF the ignition for 30 seconds. Turn ON the ignition with the engine OFF. Observe the throttle position (TP) Indicated Angle parameter with a scan tool. Depress the accelerator pedal completely. Is the TP Indicated Angle parameter within the specified range?98-100%Go to Step 9Go to DTC P0120
9Turn OFF the ignition. Inspect for the following conditions: A restricted or collapsed air intake duct A misaligned air intake duct A dirty or deteriorating air filter element Any objects blocking the air inlet screen of the mass air flow (MAF) sensor Any contamination or debris on the sensing elements of the MAF sensor Any water intrusion in the induction system Any vacuum leak downstream of the MAF sensor A skewed or stuck intake air temperature (IAT) sensor - Refer to Temperature vs Resistance A MAF sensor harness that is routed too close to any aftermarket accessories - Refer to Checking Aftermarket Accessories . Any type of restriction in the exhaust system. Did you find and correct the condition?Go to Step 14Go to Step 10
10Disconnect the harness connector of the MAF sensor. Measure the battery voltage with a DMM. Turn ON the ignition, with the engine OFF. Connect a test lamp between the ignition 1 voltage circuit of the MAF sensor and a good ground. Refer to Circuit Testing . Connect a DMM to the probe of the test lamp and a good ground. Refer to Measuring Voltage Drop . Is the voltage within 0.50 volts of the specified value?B+Go to Step 11Go to Step 12
11Test for an intermittent and for a poor connection at the MAF sensor. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition?Go to Step 14Go to Step 13
12Repair the high resistance in the ignition 1 voltage circuit of the MAF sensor. Refer to Wiring Repairs . Did you complete the repair?Go to Step 14
13Replace the MAF/IAT sensor. Refer to Mass Air Flow (MAF)/Intake Air Temperature (IAT) Sensor Replacement . Did you complete the replacement?Go to Step 14
14Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. 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. Did the DTC fail this ignition?Go to Step 2Go to Step 15
15Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed?Go to Diagnostic Trouble Code (DTC) List - VehicleSystem OK
IMPORTANT
The Altitude vs. Barometric Pressure table indicates a pressure range for a given altitude under normal weather conditions. Weather conditions consisting of very low or very high pressure and/or temperature may cause a reading to be slightly out of range.

DTC P0101

The numbers below refer to the step numbers on the diagnostic table.

  1. 5: This step will determine if any mechanical faults have caused this DTC to set.
  2. 7: This voltage drop test will determine if high resistance has caused this DTC to set.
  3. 9: This step verifies the voltage signal from the PCM to the MAF sensor connector.
  4. 10: This step tests the signal circuit of the MAF sensor for a short to another 5-volt reference circuit.
  5. 11: This step will determine if the PCM is able to process the frequency signal that it receives from the MAF sensor.
  6. 14: This step will determine which portion of the circuit or which component is shorted to ground.
  7. 17: This step verifies that the signal circuit is not shorted to any other PCM circuit.
StepActionValuesYesNo
Schematic Reference: Engine Controls Schematics Connector End View Reference: Engine Controls Connector End Views or Powertrain Control Module (PCM) Connector End Views
1Did you perform the Diagnostic System Check - Vehicle?Go to Step 2Go to Diagnostic System Check - Vehicle
2Start the engine. Observe the Mass Air Flow (MAF) Sensor parameter with a scan tool. Is the MAF Sensor parameter less than the specified value?1,200 HzGo to Step 4Go to Step 3
3Observe the Freeze Frame/Failure Records for this DTC. Turn OFF the ignition for 30 seconds. Start the engine. 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. Did the DTC fail this ignition?Go to Step 4Go to Diagnostic Aids
4Observe the MAF Sensor parameter with a scan tool. Move the harness and the connector of the MAF/intake air temperature (IAT) sensor. Does the movement of the harness or the connector affect the MAF Sensor parameter?Go to Step 20Go to Step 5
5Turn OFF the ignition. Inspect for the following conditions: A restricted or collapsed air intake duct A misaligned air intake duct A dirty or deteriorating air filter element Any objects blocking the air inlet screen of the MAF/IAT sensor Any water intrusion in the Induction System A restricted Exhaust System Any contamination or debris on the sensing elements of the MAF sensor Did you find and correct the condition?Go to Step 28Go to Step 6
6Inspect the fuse in the ignition 1 voltage circuit of the MAF sensor. Is the fuse open?Go to Step 14Go to Step 7
7Turn ON the ignition, with the engine OFF. Measure the battery voltage with a DMM. Disconnect the MAF/IAT sensor. Connect a test lamp between the ignition 1 voltage circuit of the MAF sensor and a good ground. Refer to Probing Electrical Connectors . Connect the DMM to the probe of the test lamp and a good ground. Refer to Measuring Voltage Drop and Circuit Testing . Is the voltage within 0.50 volts of the specified value?B+Go to Step 8Go to Step 21
8IMPORTANT: All electrical components and accessories must be turned OFF. Turn OFF the ignition for 60 seconds to allow the control modules to power down. Measure the resistance from the ground circuit of the MAF sensor to a good ground with a DMM. Refer to Circuit Testing . Is the resistance less than the specified value?5 ohmGo to Step 9Go to Step 22
9Turn ON the ignition, with the engine OFF. Measure the voltage from the signal circuit of the MAF sensor to a good ground with a DMM. Refer to Circuit Testing . Is the voltage within the specified range?4.8-5.2 VGo to Step 10Go to Step 13
10Connect a 3-amp fused jumper wire between the signal circuit of the MAF sensor and a good ground. Refer to Circuit Testing . IMPORTANT: Running the engine with the MAF/IAT sensor disconnected may also set DTC P0113. Start the engine. Observe the DTC Information with a scan tool. Do any additional DTCs set?Go to Step 24Go to Step 11
11Turn OFF the ignition. Connect the voltage supply and ground the black lead of the J 38522 Variable Signal Generator to the vehicle. Connect the red lead of the J 38522 to the signal circuit of the MAF sensor. Refer to Probing Electrical Connectors . Set the Duty Cycle switch of the J 38522 to Normal. Set the Frequency switch of the J 38522 to 5 K. Set the Signal switch of the J 38522 to 5 V. Start the engine and allow it to idle. Observe the MAF Sensor parameter with a scan tool. Is the MAF Sensor parameter within the specified range?4,950-5,025 HzGo to Step 12Go to Step 15
12IMPORTANT: An abnormal resistance on the signal circuit will disable the MAF sensor frequency before the voltage starts to drop out of the correct parameter of 4.8-5.2 volts. Turn OFF the ignition. Disconnect the powertrain control module (PCM). Test the MAF sensor signal circuit for a high resistance and for a short to the IAT signal circuit. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition?Go to Step 28Go to Step 18
13Is the voltage less than the specified value?4.8 VGo to Step 15Go to Step 16
14IMPORTANT: The ignition 1 voltage circuit of the MAF sensor is spliced to other components of the vehicle. Test the ignition 1 voltage circuit for a short to ground. Refer to Testing for Short to Ground and Wiring Repairs .Did you find and correct the condition?Go to Step 28
15Turn OFF the ignition. Disconnect the PCM. Test the signal circuit between the PCM and the MAF sensor for the following conditions: A high resistance An open circuit A short to ground Refer to Circuit Testing and Wiring Repairs .Did you find and correct the condition?Go to Step 28Go to Step 17
16IMPORTANT: Disconnecting the PCM connectors may eliminate the short to voltage if the signal circuit is shorted to another PCM circuit. Turn OFF the ignition. Disconnect the PCM. Turn ON the ignition, with the engine OFF. Measure the voltage from the signal circuit of the MAF sensor to a good ground with a DMM. Refer to Circuit Testing . Is the voltage more than the specified value?0 VGo to Step 23Go to Step 17
17Measure the resistance from the signal circuit of the MAF sensor to all other circuits at both PCM connectors with a DMM. Refer to Circuit Testing . Is the resistance less than the specified value?Infinity ohmGo to Step 25Go to Step 19
18Test for an intermittent and for a poor connection at the MAF sensor. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition?Go to Step 28Go to Step 26
19Test for an intermittent and for a poor connection at the PCM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition?Go to Step 28Go to Step 27
20Repair the wiring or the connector as needed. Refer to Wiring Repairs and Connector Repairs . Did you complete the repair?Go to Step 28
21Repair the high resistance or the open in the MAF sensor ignition 1 voltage circuit. Refer to Wiring Repairs . Did you complete the repair?Go to Step 28
22Repair the high resistance or the open in the MAF sensor ground circuit. Refer to Wiring Repairs . Did you complete the repair?Go to Step 28
23Repair the short to voltage in the MAF sensor signal circuit. Refer to Wiring Repairs . Did you complete the repair?Go to Step 28
24Repair the short between the MAF sensor signal circuit and the 5-volt reference circuit for which the DTC set. Refer to Wiring Repairs . Did you complete the repair?Go to Step 28
25Repair the circuits that are shorted together. Refer to Wiring Repairs . Did you complete the repair?Go to Step 28
26Replace the MAF/IAT sensor. Refer to Mass Air Flow (MAF)/Intake Air Temperature (IAT) Sensor Replacement . Did you complete the replacement?Go to Step 28
27Replace the PCM. Refer to Control Module References for replacement, setup, and programming. Did you complete the replacement?Go to Step 28
28Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. 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. Did the DTC fail this ignition?Go to Step 2Go to Step 29
29Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed?Go to Diagnostic Trouble Code (DTC) List - VehicleSystem OK
IMPORTANT
All electrical components and accessories must be turned OFF.
IMPORTANT
Running the engine with the MAF/IAT sensor disconnected may also set DTC P0113.
IMPORTANT
An abnormal resistance on the signal circuit will disable the MAF sensor frequency before the voltage starts to drop out of the correct parameter of 4.8-5.2 volts.
IMPORTANT
The ignition 1 voltage circuit of the MAF sensor is spliced to other components of the vehicle.
IMPORTANT
Disconnecting the PCM connectors may eliminate the short to voltage if the signal circuit is shorted to another PCM circuit.

DTC P0102

The numbers below refer to the step numbers on the diagnostic table.

  1. 3: This step tests for electromagnetic interference (EMI) on the signal circuit of the MAF sensor. A frequency reading with the MAF sensor disconnected indicates an EMI related fault or a poor connection at the PCM. Disconnecting the MAF sensor may set additional related DTCs.
  2. 4: This step will determine if incorrect harness routing has caused this DTC to set.
  3. 5: This step will determine if water intrusion has caused this DTC to set.
StepActionValuesYesNo
Schematic Reference: Engine Controls Schematics Connector End View Reference: Powertrain Control Module (PCM) Connector End Views or Engine Controls Connector End Views
1Did you perform the Diagnostic System Check - Vehicle?Go to Step 2Go to Diagnostic System Check - Vehicle
2Observe the Freeze Frame/Failure Records for this DTC. Turn OFF the ignition for 30 seconds. Start the engine. 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. Did the DTC fail this ignition?Go to Step 3Go to Diagnostic Aids
3Turn OFF the ignition. Disconnect the mass air flow (MAF)/intake air temperature (IAT) sensor. IMPORTANT: Running the engine with the MAF/IAT sensor disconnected may set additional MAF and IAT DTCs. Start the engine. Observe the MAF Sensor parameter with a scan tool. Is the MAF Sensor parameter more than the specified value?0 HzGo to Step 4Go to Step 5
4Turn OFF the ignition. Inspect the harness of the MAF sensor for incorrect routing that is too close to the following components: Any aftermarket accessories - Refer to Checking Aftermarket Accessories . The secondary ignition wires or the coils Any solenoids Any relays Any motors Did you find and correct the condition?Go to Step 10Go to Step 7
5Turn OFF the ignition. Inspect the air induction system for any water intrusion. Did you find and correct the condition?Go to Step 10Go to Step 6
6Test for an intermittent and for a poor connection at the MAF sensor. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition?Go to Step 10Go to Step 8
7Test for an intermittent and for a poor connection at the powertrain control module (PCM). Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition?Go to Step 10Go to Step 9
8Replace the MAF/IAT sensor. Refer to Mass Air Flow (MAF)/Intake Air Temperature (IAT) Sensor Replacement . Did you complete the replacement?Go to Step 10
9Replace the PCM. Refer to Control Module References for replacement, setup, and programming. Did you complete the replacement?Go to Step 10
10Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. 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. Did the DTC fail this ignition?Go to Step 2Go to Step 11
11Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed?Go to Diagnostic Trouble Code (DTC) List - VehicleSystem OK
IMPORTANT
Running the engine with the MAF/IAT sensor disconnected may set additional MAF and IAT DTCs.

DTC P0103

The numbers below refer to the step numbers on the diagnostic table.

  1. 5: This step tests the MAP sensors ability to correctly indicate barometric pressure.
  2. 7: This step tests the MAP sensors ability to respond to an increase in engine vacuum.
  3. 9: This step tests for a proper MAP sensor pressure with an applied vacuum.
  4. 14: This step calculates the resistance in the 5-volt reference circuit.
  5. 15: This step calculates the resistance in the low reference circuit.
StepActionValuesYesNo
Schematic Reference: Engine Controls Schematics Connector End View Reference: Engine Controls Connector End Views or Powertrain Control Module (PCM) Connector End Views
1Did you perform the Diagnostic System Check - Vehicle?Go to Step 2Go to Diagnostic System Check - Vehicle
2Are DTCs P0107 or P0108 set?Go to Diagnostic Trouble Code (DTC) List - VehicleGo to Step 3
3Inspect for the following conditions: A disconnected, damaged, or incorrectly routed vacuum hose A missing or damaged manifold absolute pressure (MAP) sensor seal Any restrictions in the MAP sensor vacuum source Any vacuum leaks in the intake manifold Did you find and correct the condition?Go to Step 22Go to Step 4
4IMPORTANT: The vehicle used for the comparison is not limited to the same type of vehicle as is being serviced. A vehicle known to provide an accurate reading is acceptable. Do you have access to another vehicle in which the MAP sensor pressure can be observed with a scan tool?Go to Step 5Go to Step 6
5Turn ON the ignition, with the engine OFF. Observe the MAP sensor pressure with the scan tool. Observe the MAP sensor pressure in the known good vehicle with the scan tool. Compare the values. Is the difference between the values less than the specified value?3 kPaGo to Step 7Go to Step 12
6IMPORTANT: The Altitude vs. Barometric Pressure table indicates a pressure range for a given altitude under normal weather conditions. Weather conditions consisting of very low or very high pressure and/or very low or very high temperature may cause a reading to be slightly out of range. Turn ON the ignition, with the engine OFF. Observe the MAP sensor pressure with the scan tool. Refer to Altitude vs Barometric Pressure . The MAP sensor pressure should be within the range specified for your altitude. Does the MAP sensor indicate the correct barometric pressure?Go to Step 7Go to Step 12
7Observe the MAP sensor pressure with the scan tool. Start the engine. Does the MAP sensor pressure change?Go to Step 8Go to Step 12
8Turn OFF the ignition. Remove the MAP sensor from the intake manifold. Leave the MAP sensor connected to the electrical harness. Connect a pump J 23738-A Mityvac to the MAP sensor port. Turn ON the ignition, with the engine OFF. Observe the MAP sensor pressure with the scan tool. Apply vacuum to the MAP sensor with the J 23738-A in 1 inch Hg increments until 15 inch Hg is reached. Each 1 inch Hg should decrease the MAP sensor pressure by 3-4 kPa. Is the decrease in MAP sensor pressure consistent?Go to Step 9Go to Step 12
9Observe the MAP sensor pressure with the scan tool. Apply vacuum with the J 23738-A until 20 inches Hg is reached. Is the MAP sensor pressure less than the specified value?34 kPaGo to Step 10Go to Step 12
10Observe the MAP sensor pressure with the scan tool. Disconnect the J 23738-A from the MAP sensor. Does the MAP sensor pressure return to the original reading observed in Step 5 or Step 6?Go to Step 11Go to Step 12
11Inspect for the following engine conditions: Incorrect cam timing - Refer to Timing Chain and Sprockets Replacement for the correct timing. A restricted exhaust flow - Refer to Restricted Exhaust . Any worn piston rings - Refer to Engine Compression Test . Did you find and correct the condition?Go to Step 22Go to Testing for Intermittent Conditions and Poor Connections
12Test for an intermittent and for a poor connection at the MAP sensor. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition?Go to Step 22Go to Step 13
13Disconnect the MAP sensor harness connector. Measure the voltage from the 5-volt reference circuit of the MAP sensor to a good ground with a DMM. Note the measurement as "Supply Voltage". Connect a test lamp and a DMM in series between the 5-volt reference circuit and the low reference circuit of the MAP sensor at the harness connector. Measure the amperage with the DMM. Note the measurement as "Amperage". Is the amperage at the specified value?0 mAGo to Step 17Go to Step 14
14Remove the DMM from the circuit. Connect the test lamp between the 5-volt reference circuit and the low reference circuit of the MAP sensor, at the harness connector. Measure the voltage from the 5-volt reference circuit at the test lamp to a good ground, with the DMM. Note the measurement as "Load voltage drop". Subtract the "Load voltage drop" from the "Supply voltage". Note the result as "Supply voltage drop". Divide the "Supply voltage drop" by the "Amperage". Is the result more than the specified value?5 ohmGo to Step 16Go to Step 15
15Measure the voltage from the low reference circuit of the MAP sensor at the test lamp to a good ground, with the DMM. Note the result as "Low reference voltage drop". Divide the "Low reference voltage drop" by the "Amperage". Is the result more than the specified value?5 ohmGo to Step 18Go to Step 20
16Test the 5-volt reference circuit between the powertrain control module (PCM) and the MAP sensor for high resistance. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition?Go to Step 22Go to Step 19
17Test the low reference circuit between the PCM and the MAP sensor for an open. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition?Go to Step 22Go to Step 19
18Test the low reference circuit between the PCM and the MAP sensor for high resistance. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition?Go to Step 22Go to Step 19
19Test for an intermittent and for a poor connection at the PCM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition?Go to Step 22Go to Step 21
20Replace the MAP sensor. Refer to Manifold Absolute Pressure (MAP) Sensor Replacement . Did you complete the replacement?Go to Step 22
21Replace the PCM. Refer to Control Module References for replacement, setup, and programming. Did you complete the replacement?Go to Step 22
22Clear the DTCs with the scan tool. Turn OFF the ignition for 30 seconds. Start the engine. 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. Did the DTC fail this ignition?Go to Step 2Go to Step 23
23Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed?Go to Diagnostic Trouble Code (DTC) List - VehicleSystem OK
IMPORTANT
The vehicle used for the comparison is not limited to the same type of vehicle as is being serviced. A vehicle known to provide an accurate reading is acceptable.
IMPORTANT
The Altitude vs. Barometric Pressure table indicates a pressure range for a given altitude under normal weather conditions. Weather conditions consisting of very low or very high pressure and/or very low or very high temperature may cause a reading to be slightly out of range.

DTC P0106

The number below refers to the step number on the diagnostic table.

  1. 7: This step tests for the proper operation of the circuit in the low voltage range.
StepActionValuesYesNo
Schematic Reference: Engine Controls Schematics Connector End View Reference: Powertrain Control Module (PCM) Connector End Views or Engine Controls Connector End Views
1Did you perform the Diagnostic System Check - Vehicle?Go to Step 2Go to Diagnostic System Check - Vehicle
2Start the engine. Monitor the DTC information with the scan tool. Is DTC P0641 also set?Go to DTC P0641Go to Step 3
3Observe the Intake Air Temperature (IAT) Sensor parameter with a scan tool. Is the IAT Sensor parameter less than the specified value?38°C (-36°F)Go to Step 5Go to Step 4
4Observe the Freeze Frame/Failure Records data for this DTC. Turn OFF the ignition for 30 seconds. Start the engine. 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. Did the DTC fail this ignition?Go to Step 5Go to Diagnostic Aids
5Disconnect the mass air flow (MAF)/IAT sensor. Connect a DMM between the signal circuit of the IAT sensor and a good ground. Is the voltage more than the specified value?5.2 VGo to Step 6Go to Step 7
6IMPORTANT: The sensor may be damaged if the circuit is shorted to a voltage source. Test the signal circuit for a short to voltage. Refer to Circuit Testing and Wiring Repairs .Did you find and correct the condition?Go to Step 16Go to Step 13
7Connect a 3-amp fused jumper wire between the signal circuit of the IAT sensor and the low reference circuit of the IAT sensor. Refer to Using Fused Jumper Wires . Observe the IAT Sensor parameter with a scan tool. Is the IAT Sensor parameter more than the specified value?128°C (262°F)Go to Step 11Go to Step 8
8Connect a 3-amp fused jumper wire between the signal circuit of the IAT sensor and a good ground. Refer to Using Fused Jumper Wires . Observe the IAT Sensor parameter with a scan tool. Is the IAT Sensor parameter more than the specified value?128°C (262°F)Go to Step 10Go to Step 9
9Test the signal circuit of the IAT sensor for an open circuit or high resistance. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition?Go to Step 16Go to Step 13
10Test the IAT sensor low reference circuit for high resistance or an open. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition?Go to Step 16Go to Step 13
11Test the IAT signal circuit for a short to any 5-volt reference circuit. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition?Go to Step 16Go to Step 12
12IMPORTANT: The sensor may be damaged if the circuit is shorted to a voltage source. Test for an intermittent and for a poor connection at the IAT sensor. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .Did you find and correct the condition?Go to Step 16Go to Step 14
13Test for an intermittent and for a poor connection at the powertrain control module (PCM). Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition?Go to Step 16Go to Step 15
14Replace the IAT sensor. Refer to Mass Air Flow (MAF)/Intake Air Temperature (IAT) Sensor Replacement . Did you complete the replacement?Go to Step 16
15Replace the PCM. Refer to Control Module References for replacement, setup, and programming. Did you complete the replacement?Go to Step 16
16Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. 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. Did the DTC fail this ignition?Go to Step 2Go to Step 17
17Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed?Go to Diagnostic Trouble Code (DTC) List - VehicleSystem OK
IMPORTANT
The sensor may be damaged if the circuit is shorted to a voltage source.
IMPORTANT
The sensor may be damaged if the circuit is shorted to a voltage source.

DTC P0113

The numbers below refer to the step numbers on the diagnostic table.

  1. 7: A snapshot is the quickest method to capture the data before it changes.
  2. 8: An IAT sensor that is skewed low can cause this DTC to set.
  3. 10: This step will determine if high resistance has caused this DTC to set.
  4. 12: A high resistance short from the signal circuit to the low reference circuit can cause this DTC to set.
StepActionValuesYesNo
Schematic Reference: Engine Controls Schematics Connector End View Reference: Engine Controls Connector End Views or Powertrain Control Module (PCM) Connector End Views
1Did you perform the Diagnostic System Check - Vehicle?Go to Step 2Go to Diagnostic System Check - Vehicle
2Inspect the cooling system coolant level. Is the cooling system coolant low?Go to Draining and Filling Cooling System (w/RPO HP2) or Draining and Filling Cooling System (w/o RPO HP2)Go to Step 3
3Observe and record the ambient air temperature of the vehicle environment using an accurate thermometer. Did you complete the action?Go to Step 4
4IMPORTANT: The vehicle needs to have been OFF for at least 10 hours for the engine coolant temperature (ECT) and the intake air temperature (IAT) to be at ambient temperature. The vehicle should not have changed environments during this time. Has the engine been OFF for the specified amount of time?10 hrsGo to Step 7Go to Step 5
5Remove the mass air flow (MAF)/IAT sensor. Refer to Mass Air Flow (MAF)/Intake Air Temperature (IAT) Sensor Replacement . Remove the ECT sensor. Refer to Engine Coolant Temperature (ECT) Sensor Replacement . Place the sensors on a work surface away from any heat source. Allow the sensors to reach the ambient air temperature for 30-60 minutes. Are the sensors at the ambient temperature?Go to Step 6
6Connect the MAF/IAT sensor to the electrical connector, but DO NOT install it. Insulate the sensor from any engine heat source. Connect the ECT sensor to the electrical connector, but DO NOT install it. Insulate the sensor from any engine heat source. Are the sensors connected?Go to Step 7
7IMPORTANT: The IAT sensor will start to warm-up as soon as the ignition is turned ON. Turn ON the ignition. Take a snapshot of the Engine Data List with a scan tool. Refer to Scan Tool Snapshot Procedure . Review the snapshot data that was taken with the scan tool. Observe the ECT Sensor parameter with a scan tool. Observe the IAT Sensor parameter with a scan tool. Is the difference between the ECT Sensor parameter and the IAT Sensor parameter more than the specified value?15°C (27°F)Go to Step 8Go to Testing for Intermittent Conditions and Poor Connections
8Observe the recorded IAT Sensor parameter. Is the difference between the IAT Sensor parameter and the ambient air temperature less than the specified value?8°C (14°F)Go to Step 9Go to Step 10
9Observe the recorded ECT Sensor parameter. Is the difference between the ECT Sensor parameter and the ambient air temperature less than the specified value?8°C (14°F)Go to Testing for Intermittent Conditions and Poor ConnectionsGo to Step 12
10Disconnect the MAF/IAT sensor. Test for an intermittent and for a poor connection at the IAT sensor. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition?Go to Step 25Go to Step 11
11At the sensor, measure the resistance between the IAT signal and the IAT low reference terminals with a DMM and record the value. Refer to Circuit Testing . Observe the recorded ambient air temperature. Compare the resistance measurement of the IAT sensor to the ambient air temperature using the Temperature vs. Resistance table. Refer to Temperature vs Resistance . Is the resistance measurement of the IAT sensor within the specified range?Go to Step 14Go to Step 22
12Disconnect the ECT sensor. Inspect for the following conditions: An ECT sensor leaking engine coolant internally through the sensor Corrosion on the ECT sensor terminals Corrosion on the ECT harness connector terminals Did you find and correct the condition?Go to Step 25Go to Step 13
13IMPORTANT: Do not hold the ECT sensor by the probe. At the sensor, measure the resistance between the ECT signal and the ECT low reference terminals with a DMM and record the value. Refer to Circuit Testing . Observe the recorded ambient air temperature. Compare the resistance measurement of the ECT sensor to the ambient air temperature using the Temperature vs. Resistance table. Refer to Temperature vs Resistance . Is the resistance measurement of the ECT sensor within the specified range?Go to Step 15Go to Step 23
14IMPORTANT: All electrical components and accessories must be turned OFF. Performing this step will disable the diagnostic for 10 hours. Turn OFF the ignition for 90 seconds to allow the control modules to power down. Measure the resistance from the low reference circuit of the IAT sensor to a good ground with a DMM. Refer to Circuit Testing . Is the resistance less than the specified value?5 ohmGo to Step 16Go to Step 17
15Measure the voltage from the ECT signal circuit to a good ground with a DMM. Refer to Circuit Testing . Is the voltage within the specified range?4.8-5.2 VGo to Testing for Intermittent Conditions and Poor ConnectionsGo to Step 19
16Disconnect the powertrain control module (PCM). Measure the resistance of the IAT sensor signal circuit between the sensor harness and the PCM with a DMM. Refer to Circuit Testing . Is the resistance within the specified range?0-10 ohmGo to Testing for Intermittent Conditions and Poor ConnectionsGo to Step 18
17Test the IAT low reference circuit for a high resistance. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition?Go to Step 25Go to Step 20
18Test the IAT signal circuit for a high resistance. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition?Go to Step 25Go to Step 20
19Test the ECT signal circuit for a high resistance short to ground. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition?Go to Step 25Go to Step 21
20Test for an intermittent and for a poor connection at the PCM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition?Go to Step 25Go to Step 24
21Test for shorted terminals and poor connections at the PCM. Refer to the following procedures: Testing for Intermittent Conditions and Poor Connections Connector Repairs Did you find and correct the condition?Go to Step 25Go to Step 24
22Replace the MAF/IAT sensor. Refer to Mass Air Flow (MAF)/Intake Air Temperature (IAT) Sensor Replacement . Did you complete the replacement?Go to Step 25
23Replace the ECT sensor. Refer to Engine Coolant Temperature (ECT) Sensor Replacement . Did you complete the replacement?Go to Step 25
24Replace the PCM. Refer to Control Module References for replacement, setup, and programming. Did you complete the replacement?Go to Step 25
25Reassemble the vehicle as necessary. Did you complete the action?Go to Step 26
26IMPORTANT: This DTC will not run without the ignition being OFF for at least 10 hours. Clear the DTCs with a scan tool. Turn OFF the ignition for 10 hours. Start the engine. Operate the vehicle within the Conditions for Running in the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records Did the DTC fail this ignition?Go to Step 2Go to Step 27
27Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed?Go to Diagnostic Trouble Code (DTC) List - VehicleSystem OK
IMPORTANT
The vehicle needs to have been OFF for at least 10 hours for the engine coolant temperature (ECT) and the intake air temperature (IAT) to be at ambient temperature. The vehicle should not have changed environments during this time.
IMPORTANT
The IAT sensor will start to warm-up as soon as the ignition is turned ON.
IMPORTANT
Do not hold the ECT sensor by the probe.
IMPORTANT
All electrical components and accessories must be turned OFF. Performing this step will disable the diagnostic for 10 hours.
IMPORTANT
This DTC will not run without the ignition being OFF for at least 10 hours.

DTC P0116

The number below refers to the step number on the diagnostic table.

  1. 33: When the TAC module detects a condition within the TAC system, more than one TAC system related DTC may set. This is due to the many redundant tests run continuously on this system. Locating and repairing one individual condition may correct more than one DTC. Disconnecting components during testing may set additional DTCs. Keep this in mind when reviewing the stored information, Capture Info.
StepActionValuesYesNo
Schematic Reference: Engine Controls Schematics Connector End View Reference: Powertrain Control Module (PCM) Connector End Views or Engine Controls Connector End Views
1Did you perform the Diagnostic System Check - Vehicle?Go to Step 2Go to Diagnostic System Check - Vehicle
2Turn OFF the ignition. Remove the air inlet duct from the throttle body. Disconnect the throttle body harness connector. Connect jumper wires between the throttle position (TP) sensor 1 terminals of the throttle body harness connector and the corresponding TP sensor 1 terminals of the throttle body. Turn ON the ignition, with the engine OFF. Close the throttle blade by hand. Observe the TP sensor 1 voltage with a scan tool. Is the TP sensor 1 voltage within the specified range?0.37-0.71 VGo to Step 5Go to Step 3
3Turn OFF the ignition. Connect jumper wires between the TP sensor 2 terminals of the throttle body harness connector and the corresponding TP sensor 2 terminals of the throttle body. Turn ON the ignition, with the engine OFF. Close the throttle blade by hand. Observe the TP sensor 2 voltage with a scan tool. Is the TP sensor 2 voltage within the specified range?0.28-0.81 VGo to Step 9Go to Step 4
4Is DTC P1518 also set?Go to Diagnostic Trouble Code (DTC) List - VehicleGo to Step 9
5Open the throttle blade to wide open throttle (WOT) by hand. Observe the TP Sensor 1 Voltage parameter on the scan tool. Is the TP Sensor 1 Voltage parameter more than the specified value?4.51 VGo to Step 9Go to Step 6
6Disconnect the TP sensor harness connector. Disconnect the throttle actuator control (TAC) module harness connector containing the TP sensor circuits. Test the TP sensor low - Reference circuit for a short to ground with a DMM. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition?Go to Step 32Go to Step 7
7Turn OFF the ignition for 15 seconds. Connect the TAC module harness connector. Connect the throttle body harness connector. Install the air inlet duct. Turn ON the ignition, with the engine OFF. Select the DTC Info option on the scan tool. Lightly touch and move the related engine wiring harnesses and connectors for the TP sensor while observing the DTC Info. The DTC will set if an intermittent condition is present. Refer to Connector Repairs and Wiring Repairs . Did you find and correct the condition?Go to Step 32Go to Step 8
8Continue to observe DTC Info. Slowly depress the accelerator pedal to WOT, then slowly return the pedal to the released position 3 times. Does the scan tool indicate this DTC failed this ignition?Go to Step 27Go to Diagnostic Aids
9Disconnect the TP sensor harness connector. Measure the voltage at the TP sensor 1 signal circuit with a DMM connected to ground. Is the voltage within the specified range?3.94-6.06 VGo to Step 14Go to Step 10
10Turn OFF the ignition. Disconnect the TAC module harness connector containing the TP sensor circuits. Turn ON the ignition, with the engine OFF. Test the TP sensor 1 signal circuit for a short to voltage with a DMM. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition?Go to Step 32Go to Step 11
11Test the TP sensor 1 signal circuit for an open or high resistance with a DMM. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition?Go to Step 32Go to Step 12
12Test the TP sensor 1 signal circuit for a short to ground with a DMM. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition?Go to Step 32Go to Step 13
13Disconnect the other TAC module harness connector. Test for a short between the TP sensor 1 signal circuit and all other TAC module circuits with a DMM. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition?Go to Step 32Go to Step 28
14Measure the voltage from the TP sensor 1, 5-volt reference circuit to a good ground with a DMM. Refer to Circuit Testing . Is the voltage within the specified range?4.54-5.21 VGo to Step 24Go to Step 15
15Is the voltage more than the specified value?5.21 VGo to Step 16Go to Step 18
16Turn OFF the ignition. Disconnect the TAC module harness connector containing the TP sensor circuits. Turn ON the ignition, with the engine OFF. Test the TP sensor 1, 5-volt reference circuit for a short to voltage with a DMM. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition?Go to Step 32Go to Step 17
17Turn OFF the ignition. Disconnect the accelerator pedal position (APP) sensor harness connector. Disconnect the other TAC module harness connector. Turn ON the ignition, with the engine OFF. Test the APP sensor 1, 5-volt reference circuit for a short to voltage with a DMM. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition?Go to Step 32Go to Step 22
18Disconnect the APP sensor. Is the voltage less than the specified value?4.54 VGo to Step 19Go to Step 30
19Disconnect the TAC module harness connector containing the TP sensor circuits. Test the TP sensor 1, 5-volt reference circuit for an open or high resistance with a DMM. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition?Go to Step 32Go to Step 20
20Test the TP sensor 1, 5-volt reference circuit for a short to ground with a DMM. Did you find and correct the condition?Go to Step 32Go to Step 21
21Test the APP sensor 1, 5-volt reference circuit for a short to ground with a DMM. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition?Go to Step 32Go to Step 22
22Test for a short between the TP sensor 1, 5-volt reference circuit and all other TAC module circuits with a DMM. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition?Go to Step 32Go to Step 23
23Test for a short between the APP sensor 1, 5-volt reference circuit and all other TAC module circuits with a DMM. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition?Go to Step 32Go to Step 28
24Connect a fused jumper between the TP sensor 1 low - Reference circuit and the TP sensor 1 signal circuit. Observe the TP Sensor 1 Voltage parameter with a scan tool. Is the TP Sensor 1 parameter near the specified value?0 VGo to Step 26Go to Step 25
25Turn OFF the ignition. Disconnect the TAC module harness connector containing the TP sensor circuits. Test the TP sensor 1 low - Reference circuit for an open or high resistance with a DMM. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition?Go to Step 32Go to Step 28
26Inspect for an intermittent and for a poor connection at the throttle body harness connector. Refer to Testing for Intermittent Conditions and Poor Connections and Repairing Connector Terminals . Did you find and correct the condition?Go to Step 32Go to Step 29
27Inspect for an intermittent and for a poor connection at the APP sensor harness connector. Refer to Testing for Intermittent Conditions and Poor Connections and Repairing Connector Terminals . Did you find and correct the condition?Go to Step 32Go to Step 30
28Inspect for an intermittent and for a poor connection at the TAC module harness connector. Refer to Testing for Intermittent Conditions and Poor Connections and Repairing Connector Terminals . Did you find and correct the condition?Go to Step 32Go to Step 31
29Replace the throttle body assembly. Refer to Throttle Body Assembly Replacement . Did you complete the replacement?Go to Step 32
30Replace the APP sensor. Refer to Accelerator Pedal with Position Sensor Replacement . Did you complete the replacement?Go to Step 32
31Replace the TAC module. Refer to Control Module References for replacement, setup, and programming. Did you complete the replacement?Go to Step 32
32Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. 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. Did the DTC fail this ignition?Go to Step 2Go to Step 33
33Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed?Go to Diagnostic Trouble Code (DTC) List - VehicleSystem OK

DTC P0120

The number below refers to the step number on the diagnostic table.

  1. 2: If the voltage is varying above and below the specified range, the condition is not present.
StepActionValue(s)YesNo
Schematic Reference: Engine Controls Schematics Connector End View Reference: Powertrain Control Module (PCM) Connector End Views or Engine Controls Connector End Views
1Did you perform the Diagnostic System Check - Vehicle?Go to Step 2Go to Diagnostic System Check - Vehicle
2Start the engine. Allow the engine to reach operating temperature. Refer to Scan Tool Data List . Observe the affected heated oxygen sensor (HO2S) voltage parameter with a scan tool. Is the HO2S voltage parameter varying above and below the specified range?300-600 mVGo to Step 3Go to Step 4
3Observe the Freeze Frame/Failure Records for this DTC. Turn OFF the ignition for 30 seconds. Start the engine. 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. Did the DTC fail this ignition?Go to Step 4Go to Testing for Intermittent Conditions and Poor Connections
4Turn OFF the ignition. Disconnect the affected HO2S. Turn ON the ignition, with the engine OFF. Observe the HO2S voltage parameter with a scan tool. Is the HO2S voltage parameter less than the specified value?100 mVGo to Step 6Go to Step 5
5Connect a 3-amp fused jumper wire between the high signal circuit of the HO2S harness connector on the engine harness side and a good ground. Observe the HO2S voltage parameter with a scan tool. Is the HO2S voltage parameter less than the specified value?100 mVGo to Step 7Go to Step 8
6Test the HO2S high signal circuit for a short to ground. Refer to the following: Heated Oxygen Sensor (HO2S) Wiring Repairs Circuit Testing Wiring Repairs Did you find and correct the condition?Go to Step 15Go to Step 9
7Test the HO2S low signal circuit for a short to the HO2S heater low control circuit. Refer to the following: Heated Oxygen Sensor (HO2S) Wiring Repairs Circuit Testing Wiring Repairs Did you find and correct the condition?Go to Step 15Go to Step 10
8Test the HO2S high signal circuit for an open or high resistance. Refer to the following: Heated Oxygen Sensor (HO2S) Wiring Repairs Circuit Testing Wiring Repairs Did you find and correct the condition?Go to Step 15Go to Step 12
9Test the HO2S high signal circuit for a short to the following circuits: HO2S low signal circuit HO2S heater low control circuit Refer to the following: Heated Oxygen Sensor (HO2S) Wiring Repairs Circuit Testing Wiring Repairs Did you find and correct the condition?Go to Step 15Go to Step 12
10The HO2S may be detecting a lean exhaust condition or may be contaminated. Inspect for the following conditions: NOTE: Refer to Silicon Contamination of Heated Oxygen Sensors Notice . A silicon contaminated HO2S Any water intrusion into the HO2S connector An exhaust leak between the HO2S and the engine Any vacuum leaks An incorrect fuel pressure - Refer to Fuel System Diagnosis . Any lean fuel injectors - Refer to Fuel Injector Balance Test with Tech 2 . An inaccurate mass air flow (MAF) sensor - Refer to Scan Tool Data List . Repair any of the above or similar engine conditions as necessary. Did you find and correct the condition?Go to Step 15Go to Step 11
11Test for shorted terminals and for poor connections at the HO2S. Refer to the following: Heated Oxygen Sensor (HO2S) Wiring Repairs Testing for Intermittent Conditions and Poor Connections Connector Repairs Did you find and correct the condition?Go to Step 15Go to Step 13
12Test for shorted terminals and for poor connections at the powertrain control module (PCM). Refer to the following: Heated Oxygen Sensor (HO2S) Wiring Repairs Testing for Intermittent Conditions and Poor Connections Connector Repairs Did you find and correct the condition?Go to Step 15Go to Step 14
13Replace the affected HO2S. Refer to Heated Oxygen Sensor (HO2S) Replacement Bank 1 Sensor 1 or Heated Oxygen Sensor (HO2S) Replacement Bank 2 Sensor 1 . Did you complete the replacement?Go to Step 15
14Replace the PCM. Refer to Control Module References for replacement, setup, and programming. Did you complete the replacement?Go to Step 15
15Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. 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. Did the DTC fail this ignition?Go to Step 2Go to Step 16
16Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed?Go to Diagnostic Trouble Code (DTC) List - VehicleSystem OK
NOTE
Refer to Silicon Contamination of Heated Oxygen Sensors Notice .

DTC P0131 or P0151

The number below refers to the step number on the diagnostic table.

  1. 2: If the voltage is varying above and below the specified range, the condition is not present.
StepActionValue(s)YesNo
Schematic Reference: Engine Controls Schematics Connector End View Reference: Powertrain Control Module (PCM) Connector End Views or Engine Controls Connector End Views
1Did you perform the Diagnostic System Check - Vehicle?Go to Step 2Go to Diagnostic System Check - Vehicle
2Start the engine. Allow the engine to reach operating temperature. Refer to Scan Tool Data List . Observe the affected heated oxygen sensor (HO2S) voltage parameter with a scan tool. Is the HO2S voltage parameter varying above and below the specified range?300-600 mVGo to Step 3Go to Step 4
3Observe the Freeze Frame/Failure Records for this DTC. Turn OFF the ignition for 30 seconds. Start the engine. 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. Did the DTC fail this ignition?Go to Step 4Go to Testing for Intermittent Conditions and Poor Connections
4Turn OFF the ignition. Disconnect the affected HO2S. Turn ON the ignition, with the engine OFF. Observe the HO2S voltage parameter with a scan tool. Is the HO2S voltage parameter within the specified range?400-500 mVGo to Step 5Go to Step 6
5Connect a 3-amp fused jumper wire between the high signal circuit of the HO2S harness connector on the engine harness side and a good ground. Observe the HO2S voltage parameter with a scan tool. Is the HO2S voltage parameter less than the specified value?100 mVGo to Step 7Go to Step 8
6Test the HO2S high signal circuit for a short to the HO2S heater low control circuit. Refer to the following: Heated Oxygen Sensor (HO2S) Wiring Repairs Circuit Testing Wiring Repairs Did you find and correct the condition?Go to Step 17Go to Step 10
7Remove the jumper wire from the previous step. Connect a 3-amp fused jumper wire between the high signal circuit of the HO2S harness connector on the engine harness side and the low signal circuit of the HO2S harness connector on the engine harness side. Observe the HO2S voltage parameter with a scan tool. Is the HO2S voltage parameter less than the specified value?100 mVGo to Step 9Go to Step 11
8Test the HO2S high signal circuit for an open or high resistance. Refer to the following: Heated Oxygen Sensor (HO2S) Wiring Repairs Circuit Testing Wiring Repairs Did you find and correct the condition?Go to Step 17Go to Step 14
9Test the HO2S low signal circuit for a short to the HO2S heater low control circuit. Refer to the following: Heated Oxygen Sensor (HO2S) Wiring Repairs Circuit Testing Wiring Repairs Did you find and correct the condition?Go to Step 17Go to Step 12
10IMPORTANT: The sensor may be damaged if the circuit is shorted to a voltage source. Test the HO2S high signal circuit for a short to voltage. Refer to the following: Heated Oxygen Sensor (HO2S) Wiring Repairs Circuit Testing Wiring Repairs Did you find and correct the condition?Go to Step 17Go to Step 14
11Test the HO2S low signal circuit for an open or high resistance. Refer to the following: Heated Oxygen Sensor (HO2S) Wiring Repairs Circuit Testing Wiring Repairs Did you find and correct the condition?Go to Step 17Go to Step 14
12The HO2S may be detecting a rich exhaust condition or may be contaminated. Inspect for the following conditions: NOTE: Refer to Silicon Contamination of Heated Oxygen Sensors Notice . A silicon contaminated HO2S Any water intrusion into the HO2S connector Engine oil contaminated with fuel An evaporative emission (EVAP) canister purge condition An incorrect fuel pressure - Refer to Fuel System Diagnosis . Any rich fuel injectors - Refer to Fuel Injector Balance Test with Tech 2 . An inaccurate mass air flow (MAF) sensor - Refer to Scan Tool Data List . An air intake restriction or collapsed air intake duct Repair any of the above or similar engine conditions as necessary. Did you find and correct the condition?Go to Step 17Go to Step 13
13Test for shorted terminals and for poor connections at the HO2S. Refer to the following: Heated Oxygen Sensor (HO2S) Wiring Repairs Testing for Intermittent Conditions and Poor Connections Connector Repairs Did you find and correct the condition?Go to Step 17Go to Step 15
14Test for shorted terminals and for poor connections at the powertrain control module (PCM). Refer to the following: Heated Oxygen Sensor (HO2S) Wiring Repairs Testing for Intermittent Conditions and Poor Connections Connector Repairs Did you find and correct the condition?Go to Step 17Go to Step 16
15Replace the affected HO2S. Refer to Heated Oxygen Sensor (HO2S) Replacement Bank 1 Sensor 1 or Heated Oxygen Sensor (HO2S) Replacement Bank 2 Sensor 1 . Did you complete the replacement?Go to Step 17
16Replace the PCM. Refer to Control Module References for replacement, setup, and programming. Did you complete the replacement?Go to Step 17
17Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. 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. Did the DTC fail this ignition?Go to Step 2Go to Step 18
18Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed?Go to Diagnostic Trouble Code (DTC) List - VehicleSystem OK
IMPORTANT
The sensor may be damaged if the circuit is shorted to a voltage source.
NOTE
Refer to Silicon Contamination of Heated Oxygen Sensors Notice .

DTC P0132 or P0152

The number below refers to the step number on the diagnostic table.

  1. 2: If the voltage is varying above and below the specified value, the condition is not present.
StepActionValue(s)YesNo
Schematic Reference: Engine Controls Schematics Connector End View Reference: Powertrain Control Module (PCM) Connector End Views or Engine Controls Connector End Views
1Did you perform the Diagnostic System Check - Vehicle?Go to Step 2Go to Diagnostic System Check - Vehicle
2Start the engine. Allow the engine to reach operating temperature. Refer to Scan Tool Data List . Operate the engine at 1,500 RPM for 30 seconds. Observe the affected HO2S voltage parameter with a scan tool. Is the HO2S voltage parameter varying above and below the specified range?250-625 mVGo to Step 3Go to Step 4
3Observe the Freeze Frame/Failure Records for this DTC. Turn OFF the ignition for 30 seconds. Start the engine. 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. Did the DTC fail this ignition?Go to Step 4Go to Testing for Intermittent Conditions and Poor Connections
4Turn OFF the ignition. Disconnect the affected heated oxygen sensor (HO2S). Connect a 3-amp fused jumper wire between the high signal circuit of the HO2S harness connector on the engine harness side and a good ground. Turn ON the ignition, with the engine OFF. Observe the HO2S voltage parameter with a scan tool. Is the HO2S voltage parameter less than the specified value?100 mVGo to Step 6Go to Step 5
5Test the HO2S high signal circuit for an open or high resistance. Refer to the following procedures: Heated Oxygen Sensor (HO2S) Wiring Repairs Circuit Testing Wiring Repairs Did you find and correct the condition?Go to Step 12Go to Step 9
6Remove the jumper wire from the previous step. Connect a 3-amp fused jumper wire between the high signal circuit of the HO2S harness connector on the engine harness side and the low signal circuit of the HO2S harness connector on the engine harness side. Observe the HO2S voltage parameter with a scan tool. Is the HO2S voltage parameter less than the specified value?100 mVGo to Step 8Go to Step 7
7Test the HO2S low signal circuit for an open or high resistance. Refer to the following procedures: Heated Oxygen Sensor (HO2S) Wiring Repairs Circuit Testing Wiring Repairs Did you find and correct the condition?Go to Step 12Go to Step 9
8Test for shorted terminals and for poor connections at the HO2S. Refer to the following procedures: Heated Oxygen Sensor (HO2S) Wiring Repairs Testing for Intermittent Conditions and Poor Connections Connector Repairs Did you find and correct the condition?Go to Step 12Go to Step 10
9Test for shorted terminals and for poor connections at the powertrain control module (PCM). Refer to the following procedures: Heated Oxygen Sensor (HO2S) Wiring Repairs Testing for Intermittent Conditions and Poor Connections Connector Repairs Did you find and correct the condition?Go to Step 12Go to Step 11
10NOTE: Refer to Silicon Contamination of Heated Oxygen Sensors Notice . IMPORTANT: The HO2S may be damaged due to contamination. Prior to replacing the HO2S inspect for the following sources of contamination: A silicon contaminated HO2S Fuel contamination - Refer to Alcohol/Contaminants-in-Fuel Diagnosis (Without Special Tool) or Alcohol/Contaminants-in-Fuel Diagnosis (With Special Tool) . Engine oil consumption - Refer to Oil Consumption Diagnosis . Engine coolant consumption - Refer to Loss of Coolant . Replace the affected HO2S. Refer to Heated Oxygen Sensor (HO2S) Replacement Bank 1 Sensor 1 or Heated Oxygen Sensor (HO2S) Replacement Bank 2 Sensor 1 .Did you complete the replacement?Go to Step 12
11Replace the PCM. Refer to Control Module References for replacement, setup, and programming. Did you complete the replacement?Go to Step 12
12Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. 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. Did the DTC fail this ignition?Go to Step 2Go to Step 13
13Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed?Go to Diagnostic Trouble Code (DTC) List - VehicleSystem OK
NOTE
Refer to Silicon Contamination of Heated Oxygen Sensors Notice .
IMPORTANT
The HO2S may be damaged due to contamination. Prior to replacing the HO2S inspect for the following sources of contamination

DTC P0133 or P0153

The number below refers to the step number on the diagnostic table.

  1. 3: If the voltage is varying above and below the specified value, the condition is not present.
StepActionValue(s)YesNo
Schematic Reference: Engine Controls Schematics Connector End View Reference: Powertrain Control Module (PCM) Connector End Views or Engine Controls Connector End Views
1Did you perform the Diagnostic System Check - Vehicle?Go to Step 2Go to Diagnostic System Check - Vehicle
2IMPORTANT: When the heated oxygen sensor (HO2S) heaters are commanded ON with a scan tool, they will continue to be pulsed ON once per second until the ignition is turned OFF for 30 seconds. Turn ON the ignition, with the engine OFF. Command the HO2S heaters ON with a scan tool. Wait 15 seconds to allow the HO2S heater current to stabilize. Observe the affected HO2S heater current parameter with a scan tool. Is the HO2S heater current parameter within the specified range?0.25-3.125 AGo to Step 3Go to DTC P0135, P0141, P0155, or P0161
3Start the engine. Allow the engine to reach operating temperature. Refer to Scan Tool Data List . Operate the engine at 1,500 RPM for 30 seconds. Observe the affected HO2S voltage parameter with a scan tool. Is the HO2S voltage parameter varying above and below the specified range?300-600 mVGo to Step 4Go to Step 5
4Observe the Freeze Frame/Failure Records for this DTC. Turn OFF the ignition for 30 seconds. Start the engine. 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. Did the DTC fail this ignition?Go to Step 5Go to Testing for Intermittent Conditions and Poor Connections
5Turn OFF the ignition. Disconnect the affected HO2S. Turn ON the ignition, with the engine OFF. Observe the HO2S voltage parameter with a scan tool. Is the HO2S voltage parameter more than the specified value?800 mVGo to Step 7Go to Step 6
6Measure the voltage from the high signal circuit of the HO2S harness connector on the engine harness side to a good ground with a DMM. Refer to Circuit Testing . Is the voltage more than the specified value?0.2 VGo to Step 8Go to Step 9
7IMPORTANT: The sensor may be damaged if the circuit is shorted to a voltage source. Test the HO2S high signal circuit for a short to voltage. Refer to the following procedures: Heated Oxygen Sensor (HO2S) Wiring Repairs Circuit Testing Wiring Repairs Did you find and correct the condition?Go to Step 17Go to Step 14
8Measure the voltage from the low signal circuit of the HO2S harness connector on the engine harness side to a good ground with a DMM. Refer to Circuit Testing . Is the voltage more than the specified value?2 VGo to Step 12Go to Step 10
9Test the HO2S high signal circuit for an open or high resistance. Refer to the following procedures: Heated Oxygen Sensor (HO2S) Wiring Repairs Circuit Testing Wiring Repairs Did you find and correct the condition?Go to Step 17Go to Step 14
10Connect a 3-amp fused jumper wire between the high signal circuit of the HO2S harness connector on the engine harness side and the low signal circuit of the HO2S harness connector on the engine harness side. Observe the HO2S voltage parameter with a scan tool. Is the HO2S voltage parameter less than the specified value?100 mVGo to Step 13Go to Step 11
11Test the HO2S low signal circuit for an open or high resistance. Refer to the following procedures: Heated Oxygen Sensor (HO2S) Wiring Repairs Circuit Testing Wiring Repairs Did you find and correct the condition?Go to Step 17Go to Step 14
12Test the HO2S low signal circuit for a short to voltage. Refer to the following procedures: Heated Oxygen Sensor (HO2S) Wiring Repairs Circuit Testing Wiring Repairs Did you find and correct the condition?Go to Step 17Go to Step 14
13Test for shorted terminals and for poor connections at the HO2S. Refer to the following procedures: Heated Oxygen Sensor (HO2S) Wiring Repairs Testing for Intermittent Conditions and Poor Connections Connector Repairs Did you find and correct the condition?Go to Step 17Go to Step 15
14Test for shorted terminals and for poor connections at the powertrain control module (PCM). Refer to the following procedures: Heated Oxygen Sensor (HO2S) Wiring Repairs Testing for Intermittent Conditions and Poor Connections Connector Repairs Did you find and correct the condition?Go to Step 17Go to Step 16
15Replace the affected HO2S. Refer to Heated Oxygen Sensor (HO2S) Replacement Bank 1 Sensor 1 or Heated Oxygen Sensor (HO2S) Replacement Bank 2 Sensor 1 . Did you complete the replacement?Go to Step 17
16Replace the PCM. Refer to Control Module References for replacement, setup, and programming. Did you complete the replacement?Go to Step 17
17Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. 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. Did the DTC fail this ignition?Go to Step 2Go to Step 18
18Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed?Go to Diagnostic Trouble Code (DTC) List - VehicleSystem OK
IMPORTANT
When the heated oxygen sensor (HO2S) heaters are commanded ON with a scan tool, they will continue to be pulsed ON once per second until the ignition is turned OFF for 30 seconds.
IMPORTANT
The sensor may be damaged if the circuit is shorted to a voltage source.

DTC P0134 or P0154

The number below refers to the step number on the diagnostic table.

  1. 9: With no fault present, the test lamp will blink once per second.
StepActionValue(s)YesNo
Schematic Reference: Engine Controls Schematics Connector End View Reference: Powertrain Control Module (PCM) Connector End Views or Engine Controls Connector End Views
1Did you perform the Diagnostic System Check - Vehicle?Go to Step 2Go to Diagnostic System Check - Vehicle
2IMPORTANT: Whenever the heated oxygen sensor (HO2S) heaters are commanded ON with a scan tool, they will continue to be pulsed ON once per second until the ignition is turned OFF for 30 seconds. Turn ON the ignition, with the engine OFF. Command the HO2S heaters ON with a scan tool. Wait 15 seconds to allow the HO2S heater current to stabilize. Observe the affected HO2S heater current parameter with a scan tool. Is the HO2S heater current parameter within the specified range?0.25-3.125 AGo to Step 3Go to Step 6
3Observe the Freeze Frame/Failure Records for this DTC. Did the DTC fail with an engine run time of less than 10 seconds?Go to Step 4Go to Step 5
4Operate the vehicle within the conditions for running the Heater Resistance Test. Start the engine. Did the DTC fail this ignition?Go to Step 6Go to Testing for Intermittent Conditions and Poor Connections
5Observe the Freeze Frame/Failure Records for this DTC. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running the Heater Current Test. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records. Did the DTC fail this ignition?Go to Step 6Go to Testing for Intermittent Conditions and Poor Connections
6Inspect the O2A or O2B fuse. Is the O2A or O2B fuse open?Go to Step 7Go to Step 8
7Test the ignition 1 voltage circuit for a short to ground. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition?Go to Step 22Go to Step 10
8Disconnect the affected HO2S. Turn ON the ignition, with the engine OFF. Probe the ignition 1 voltage circuit of the HO2S harness connector on the engine harness side with a test lamp that is connected to a good ground. Refer to Probing Electrical Connectors . Does the test lamp illuminate?Go to Step 9Go to Step 19
9IMPORTANT: The test lamp may blink prior to commanding the heaters ON. This is because the heaters were commanded ON in a previous step. To command the heaters OFF, turn OFF the ignition for 30 seconds. Connect a test lamp between the ignition 1 voltage circuit of the HO2S harness connector on the engine harness side and the HO2S heater low control circuit of the HO2S harness connector on the engine harness side. Command the HO2S heaters ON with a scan tool. Does the test lamp blink once per second?Go to Step 11Go to Step 12
10IMPORTANT: Perform the following test on all HO2S' which are supplied voltage by the suspect circuit. Test the ignition 1 voltage circuit on the sensor side of the HO2S connector for a short to ground. Refer to Circuit Testing .Is any sensor shorted to ground?Go to Step 20Go to Testing for Intermittent Conditions and Poor Connections
11Measure the resistance of the following circuits with a DMM: HO2S heater low control circuit Ignition 1 voltage circuit Refer to Circuit Testing . Is the resistance of either circuit more than the specified value?3 ohmGo to Step 18Go to Step 16
12Is the test lamp on steady?Go to Step 13Go to Step 14
13Test the HO2S heater low control circuit for a short to ground. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition?Go to Step 22Go to Step 17
14Test the HO2S heater low control circuit for a short to voltage. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition?Go to Step 22Go to Step 15
15Test the HO2S heater low control circuit for an open or high resistance. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition?Go to Step 22Go to Step 17
16Test for shorted terminals and for poor connections at the HO2S. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition?Go to Step 22Go to Step 20
17Test for shorted terminals and for poor connections at the powertrain control module (PCM). Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition?Go to Step 22Go to Step 21
18Repair the circuit with high resistance. Refer to Wiring Repairs . Did you complete the repair?Go to Step 22
19Repair the open or high resistance in the ignition 1 voltage circuit. Refer to Wiring Repairs . Did you complete the repair?Go to Step 22
20Replace the affected HO2S. Refer to the appropriate procedure: Heated Oxygen Sensor (HO2S) Replacement Bank 1 Sensor 1 Heated Oxygen Sensor (HO2S) Replacement Bank 2 Sensor 1 Heated Oxygen Sensor (HO2S) Replacement Bank 1 Sensor 2 Heated Oxygen Sensor (HO2S) Replacement Bank 2 Sensor 2 Did you complete the replacement?Go to Step 22
21Replace the PCM. Refer to Control Module References for replacement, setup, and programming. Did you complete the replacement?Go to Step 22
22Were you sent to this diagnostic from DTC P0134 or P0154?Go to Step 17 in DTC P0134 or P0154Go to Step 23
23Were you sent to this diagnostic from DTC P0140 or P0160?Go to Step 17 in DTC P0140 or P0160Go to Step 24
24Replace the O2A or O2B fuse if necessary. Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. 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. Did the DTC fail this ignition?Go to Step 2Go to Step 25
25Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed?Go to Diagnostic Trouble Code (DTC) List - VehicleSystem OK
IMPORTANT
Whenever the heated oxygen sensor (HO2S) heaters are commanded ON with a scan tool, they will continue to be pulsed ON once per second until the ignition is turned OFF for 30 seconds.
IMPORTANT
The test lamp may blink prior to commanding the heaters ON. This is because the heaters were commanded ON in a previous step. To command the heaters OFF, turn OFF the ignition for 30 seconds.
IMPORTANT
Perform the following test on all HO2S' which are supplied voltage by the suspect circuit.

DTC P0135, P0141, P0155, or P0161

The number below refers to the step number on the diagnostic table.

  1. 2: If the voltage does not change more that the specified value, the condition is present.
StepActionValue(s)YesNo
Schematic Reference: Engine Controls Schematics Connector End View Reference: Engine Controls Connector End Views or Powertrain Control Module (PCM) Connector End Views
1Did you perform the Diagnostic System Check - Vehicle?Go to Step 2Go to Diagnostic System Check - Vehicle
2IMPORTANT: With the engine running, observe the HO2S Bank 1 Sensor 1 and HO2S Bank 2 Sensor 1 voltage parameters with a scan tool. The voltage should vary from less than 300 mV to greater than 600 mV. If the voltage is not varying, refer to DTC P0132 or P0152 (without HP2) or DTC P0132 or P0152 (with HP2) . Start the engine. Allow the engine to reach operating temperature. Refer to Scan Tool Data List . Operate the engine at 1,500 RPM for 30 seconds. While observing the affected HO2S voltage parameter with a scan tool, quickly cycle the throttle from closed throttle to wide open throttle, 3 times. Did the HO2S voltage parameter change more than the specified value?200 mVGo to Step 3Go to Step 4
3Observe the Freeze Frame/Failure Records for this DTC. Turn OFF the ignition for 30 seconds. Start the engine. 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. Did the DTC fail this ignition?Go to Step 4Go to Testing for Intermittent Conditions and Poor Connections
4Turn OFF the ignition. Disconnect the affected heated oxygen sensor (HO2S). Turn ON the ignition, with the engine OFF. Observe the HO2S voltage parameter with a scan tool. Is the HO2S voltage parameter less than the specified value?100 mVGo to Step 6Go to Step 5
5Observe the HO2S voltage parameter with a scan tool. Is the HO2S voltage parameter more than the specified value?800 mVGo to Step 7Go to Step 8
6Test the HO2S high signal circuit for a short to ground. Refer to the following procedures: Heated Oxygen Sensor (HO2S) Wiring Repairs Circuit Testing Wiring Repairs Did you find and correct the condition?Go to Step 20Go to Step 9
7IMPORTANT: The sensor may be damaged if the circuit is shorted to a voltage source. Test the HO2S high signal circuit for a short to voltage. Refer to the following procedures: Heated Oxygen Sensor (HO2S) Wiring Repairs Circuit Testing Wiring Repairs Did you find and correct the condition?Go to Step 20Go to Step 17
8Measure the voltage from the low signal circuit of the HO2S harness connector on the engine harness side to a good ground with a DMM. Refer to Circuit Testing . Is the voltage more than the specified value?2 VGo to Step 10Go to Step 11
9Test the HO2S high signal circuit for a short to the HO2S low signal circuit. Refer to the following procedures: Heated Oxygen Sensor (HO2S) Wiring Repairs Circuit Testing Wiring Repairs Did you find and correct the condition?Go to Step 20Go to Step 17
10Test the HO2S low signal circuit for a short to voltage. Refer to the following procedures: Heated Oxygen Sensor (HO2S) Wiring Repairs Circuit Testing Wiring Repairs Did you find and correct the condition?Go to Step 20Go to Step 17
11Connect a 3-amp fused jumper wire between the high signal circuit of the HO2S harness connector on the engine harness side and a good ground. Observe the HO2S voltage parameter with a scan tool. Is the HO2S voltage parameter less than the specified value?100 mVGo to Step 12Go to Step 14
12Remove the jumper wire from the previous step. Connect a 3-amp fused jumper wire between the high signal circuit of the HO2S harness connector on the engine harness side and the low signal circuit of the HO2S harness connector on the engine harness side. Observe the HO2S voltage parameter with a scan tool. Is the HO2S voltage parameter less than the specified value?100 mVGo to Step 15Go to Step 13
13Test the HO2S low signal circuit for an open or high resistance. Refer to the following procedures: Heated Oxygen Sensor (HO2S) Wiring Repairs Circuit Testing Wiring Repairs Did you find and correct the condition?Go to Step 20Go to Step 17
14Test the HO2S high signal circuit for an open or high resistance. Refer to the following procedures: Heated Oxygen Sensor (HO2S) Wiring Repairs Circuit Testing Wiring Repairs Did you find and correct the condition?Go to Step 20Go to Step 17
15The HO2S may be detecting a lean exhaust condition or may be contaminated. Inspect for the following conditions: NOTE: Refer to Silicon Contamination of Heated Oxygen Sensors Notice . A silicon contaminated HO2S Any water intrusion into the HO2S connector An exhaust leak between the HO2S and the engine Any vacuum leaks An incorrect fuel pressure - Refer to Fuel System Diagnosis . Any lean fuel injectors - Refer to Fuel Injector Balance Test with Tech 2 . An inaccurate mass air flow (MAF) sensor - Refer to Scan Tool Data List . Repair any of the above or similar engine conditions as necessary. Did you find and correct the condition?Go to Step 20Go to Step 16
16Test for shorted terminals and for poor connections at the HO2S. Refer to the following procedures: Heated Oxygen Sensor (HO2S) Wiring Repairs Testing for Intermittent Conditions and Poor Connections Connector Repairs Did you find and correct the condition?Go to Step 20Go to Step 18
17Test for shorted terminals and for poor connections at the powertrain control module (PCM). Refer to the following procedures: Heated Oxygen Sensor (HO2S) Wiring Repairs Testing for Intermittent Conditions and Poor Connections Connector Repairs Did you find and correct the condition?Go to Step 20Go to Step 19
18Replace the affected HO2S. Refer to Heated Oxygen Sensor (HO2S) Replacement Bank 1 Sensor 2 or Heated Oxygen Sensor (HO2S) Replacement Bank 2 Sensor 2 . Did you complete the replacement?Go to Step 20
19Replace the PCM. Refer to Control Module References for replacement, setup, and programming. Did you complete the replacement?Go to Step 20
20Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. 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. Did the DTC fail this ignition?Go to Step 2Go to Step 21
21Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed?Go to Diagnostic Trouble Code (DTC) List - VehicleSystem OK
IMPORTANT
With the engine running, observe the HO2S Bank 1 Sensor 1 and HO2S Bank 2 Sensor 1 voltage parameters with a scan tool. The voltage should vary from less than 300 mV to greater than 600 mV. If the voltage is not varying, refer to DTC P0132 or P0152 (without HP2) or DTC P0132 or P0152 (with HP2) .
IMPORTANT
The sensor may be damaged if the circuit is shorted to a voltage source.
NOTE
Refer to Silicon Contamination of Heated Oxygen Sensors Notice .

DTC P0137 or P0157

The number below refers to the step number on the diagnostic table.

  1. 2: If the voltage does not change more that the specified value, the condition is present.
StepActionValue(s)YesNo
Schematic Reference: Engine Controls Schematics Connector End View Reference: Engine Controls Connector End Views or Powertrain Control Module (PCM) Connector End Views
1Did you perform the Diagnostic System Check - Vehicle?Go to Step 2Go to Diagnostic System Check - Vehicle
2IMPORTANT: With the engine running, observe the HO2S Bank 1 Sensor 1 and HO2S Bank 2 Sensor 1 voltage parameters with a scan tool. The voltage should vary from less than 300 mV to greater than 600 mV. If the voltage is not varying, refer to DTC P0131 or P0151 (without HP2) or DTC P0131 or P0151 (with HP2) . Start the engine. Allow the engine to reach operating temperature. Refer to Scan Tool Data List . Operate the engine at 1,500 RPM for 30 seconds. While observing the affected HO2S voltage parameter with a scan tool, quickly cycle the throttle from closed throttle to wide open throttle, 3 times. Did the HO2S voltage parameter change more than the specified value?200 mVGo to Step 3Go to Step 4
3Observe the Freeze Frame/Failure Records for this DTC. Turn OFF the ignition for 30 seconds. Start the engine. 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. Did the DTC fail this ignition?Go to Step 4Go to Testing for Intermittent Conditions and Poor Connections
4Turn OFF the ignition. Disconnect the affected heated oxygen sensor (HO2S). Turn ON the ignition, with the engine OFF. Observe the HO2S voltage parameter with a scan tool. Is the HO2S voltage parameter more than the specified value?800 mVGo to Step 6Go to Step 5
5Measure the voltage from the low signal circuit of the HO2S harness connector on the engine harness side to a good ground with a DMM. Refer to Circuit Testing . Is the voltage more than the specified value?2 VGo to Step 7Go to Step 8
6IMPORTANT: The sensor may be damaged if the circuit is shorted to a voltage source. Test the HO2S high signal circuit for a short to voltage. Refer to the following procedures: Heated Oxygen Sensor (HO2S) Wiring Repairs Circuit Testing Wiring Repairs Did you find and correct the condition?Go to Step 17Go to Step 14
7Test the HO2S low signal circuit for a short to voltage. Refer to the following procedures: Heated Oxygen Sensor (HO2S) Wiring Repairs Circuit Testing Wiring Repairs Did you find and correct the condition?Go to Step 17Go to Step 14
8Connect a 3-amp fused jumper wire between the high signal circuit of the HO2S harness connector on the engine harness side and a good ground. Observe the HO2S voltage parameter with a scan tool. Is the HO2S voltage parameter less than the specified value?100 mVGo to Step 9Go to Step 11
9Remove the jumper wire from the previous step. Connect a 3-amp fused jumper wire between the high signal circuit of the HO2S harness connector on the engine harness side and the low signal circuit of the HO2S harness connector on the engine harness side. Observe the HO2S voltage parameter with a scan tool. Is the HO2S voltage parameter less than the specified value?100 mVGo to Step 12Go to Step 10
10Test the HO2S low signal circuit for an open or high resistance. Refer to the following procedures: Heated Oxygen Sensor (HO2S) Wiring Repairs Circuit Testing Wiring Repairs Did you find and correct the condition?Go to Step 17Go to Step 14
11Test the HO2S high signal circuit for an open or high resistance. Refer to the following procedures: Heated Oxygen Sensor (HO2S) Wiring Repairs Circuit Testing Wiring Repairs Did you find and correct the condition?Go to Step 17Go to Step 14
12The HO2S may be detecting a rich exhaust condition or may be contaminated. Inspect for the following conditions: NOTE: Refer to Silicon Contamination of Heated Oxygen Sensors Notice . A silicon contaminated HO2S Any water intrusion into the HO2S connector Engine oil contaminated with fuel An EVAP canister purge condition An incorrect fuel pressure - Refer to Fuel System Diagnosis . Any rich fuel injectors - Refer to Fuel Injector Balance Test with Tech 2 . An inaccurate mass air flow (MAF) sensor - Refer to Scan Tool Data List . An air intake restriction or collapsed air intake duct Repair any of the above or similar engine conditions as necessary. Did you find and correct the condition?Go to Step 17Go to Step 13
13Test for shorted terminals and for poor connections at the HO2S. Refer to the following procedures: Heated Oxygen Sensor (HO2S) Wiring Repairs Testing for Intermittent Conditions and Poor Connections Connector Repairs Did you find and correct the condition?Go to Step 17Go to Step 15
14Test for shorted terminals and for poor connections at the powertrain control module (PCM). Refer to the following procedures: Heated Oxygen Sensor (HO2S) Wiring Repairs Testing for Intermittent Conditions and Poor Connections Connector Repairs Did you find and correct the condition?Go to Step 17Go to Step 16
15Replace the affected HO2S. Refer to Heated Oxygen Sensor (HO2S) Replacement Bank 1 Sensor 2 or Heated Oxygen Sensor (HO2S) Replacement Bank 2 Sensor 2 . Did you complete the replacement?Go to Step 17
16Replace the PCM. Refer to Control Module References for replacement, setup, and programming. Did you complete the replacement?Go to Step 17
17Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. 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. Did the DTC fail this ignition?Go to Step 2Go to Step 18
18Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed?Go to Diagnostic Trouble Code (DTC) List - VehicleSystem OK
IMPORTANT
With the engine running, observe the HO2S Bank 1 Sensor 1 and HO2S Bank 2 Sensor 1 voltage parameters with a scan tool. The voltage should vary from less than 300 mV to greater than 600 mV. If the voltage is not varying, refer to DTC P0131 or P0151 (without HP2) or DTC P0131 or P0151 (with HP2) .
IMPORTANT
The sensor may be damaged if the circuit is shorted to a voltage source.
NOTE
Refer to Silicon Contamination of Heated Oxygen Sensors Notice .

DTC P0138 or P0158

The number below refers to the step number on the diagnostic table.

  1. 3: If the voltage is varying above and below the specified value, the condition is not present.
StepActionValue(s)YesNo
Schematic Reference: Engine Controls Schematics Connector End View Reference: Powertrain Control Module (PCM) Connector End Views or Engine Controls Connector End Views
1Did you perform the Diagnostic System Check - Vehicle?Go to Step 2Go to Diagnostic System Check - Vehicle
2IMPORTANT: When the heated oxygen sensor (HO2S) heaters are commanded ON with a scan tool, they will continue to be pulsed ON once per second until the ignition is turned OFF for 30 seconds. Turn ON the ignition, with the engine OFF. Command the HO2S heaters ON with a scan tool. Wait 15 seconds to allow the HO2S heater current to stabilize. Observe the affected HO2S heater current parameter with a scan tool. Is the HO2S heater current parameter within the specified range?0.25-3.125 AGo to Step 3Go to DTC P0135, P0141, P0155, or P0161
3Start the engine. Allow the engine to reach operating temperature. Refer to Scan Tool Data List . Operate the engine at 1,500 RPM for 30 seconds. While observing the affected HO2S voltage parameter with a scan tool, quickly cycle the throttle from closed throttle to wide open throttle, 3 times. Did the HO2S voltage parameter change more than the specified value?200 mVGo to Step 4Go to Step 5
4Observe the Freeze Frame/Failure Records for this DTC. Turn OFF the ignition for 30 seconds. Start the engine. 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. Did the DTC fail this ignition?Go to Step 5Go to Testing for Intermittent Conditions and Poor Connections
5Turn OFF the ignition. Disconnect the affected HO2S. Turn ON the ignition, with the engine OFF. Observe the HO2S voltage parameter with a scan tool. Is the HO2S voltage parameter more than the specified value?800 mVGo to Step 7Go to Step 6
6Measure the voltage from the high signal circuit of the HO2S harness connector on the engine harness side to a good ground with a DMM. Refer to Circuit Testing Is the voltage more than the specified value?0.2 VGo to Step 8Go to Step 9
7IMPORTANT: The sensor may be damaged if the circuit is shorted to a voltage source. Test the HO2S high signal circuit for a short to voltage. Refer to the following procedures: Heated Oxygen Sensor (HO2S) Wiring Repairs Circuit Testing Wiring Repairs Did you find and correct the condition?Go to Step 17Go to Step 14
8Measure the voltage from the low signal circuit of the HO2S harness connector on the engine harness side to a good ground with a DMM. Refer to Circuit Testing . Is the voltage more than the specified value?2 VGo to Step 12Go to Step 10
9Test the HO2S high signal circuit for an open or high resistance. Refer to the following procedures: Heated Oxygen Sensor (HO2S) Wiring Repairs Circuit Testing Wiring Repairs Did you find and correct the condition?Go to Step 17Go to Step 14
10Connect a 3-amp fused jumper wire between the high signal circuit of the HO2S harness connector on the engine harness side and the low signal circuit of the HO2S harness connector on the engine harness side. Observe the HO2S voltage parameter with a scan tool. Is the HO2S voltage parameter less than the specified value?100 mVGo to Step 13Go to Step 11
11Test the HO2S low signal circuit for an open or high resistance. Refer to the following procedures: Heated Oxygen Sensor (HO2S) Wiring Repairs Circuit Testing Wiring Repairs Did you find and correct the condition?Go to Step 17Go to Step 14
12Test the HO2S low signal circuit for a short to voltage. Refer to the following procedures: Heated Oxygen Sensor (HO2S) Wiring Repairs Circuit Testing Wiring Repairs Did you find and correct the condition?Go to Step 17Go to Step 14
13Test for shorted terminals and for poor connections at the HO2S. Refer to the following procedures: Heated Oxygen Sensor (HO2S) Wiring Repairs Testing for Intermittent Conditions and Poor Connections Connector Repairs Did you find and correct the condition?Go to Step 17Go to Step 15
14Test for shorted terminals and for poor connections at the powertrain control module (PCM). Refer to the following procedures: Heated Oxygen Sensor (HO2S) Wiring Repairs Testing for Intermittent Conditions and Poor Connections Connector Repairs Did you find and correct the condition?Go to Step 17Go to Step 16
15Replace the affected HO2S. Refer to Heated Oxygen Sensor (HO2S) Replacement Bank 1 Sensor 2 or Heated Oxygen Sensor (HO2S) Replacement Bank 2 Sensor 2 . Did you complete the replacement?Go to Step 17
16Replace the PCM. Refer to Control Module References for replacement, setup, and programming. Did you complete the replacement?Go to Step 17
17Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. 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. Did the DTC fail this ignition?Go to Step 2Go to Step 18
18Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed?Go to Diagnostic Trouble Code (DTC) List - VehicleSystem OK
IMPORTANT
When the heated oxygen sensor (HO2S) heaters are commanded ON with a scan tool, they will continue to be pulsed ON once per second until the ignition is turned OFF for 30 seconds.
IMPORTANT
The sensor may be damaged if the circuit is shorted to a voltage source.

DTC P0140 or P0160