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Home >> Buick >> 2007 >> Allure CXS >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System & Fuel System - 3.6L - DTC P167A To P2229 >> DTC P2196 >> Test Description
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Test Description

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

  1. 2:  This step determines if a condition exists.
  2. 5:  This step is testing for a rear HO2S sensor circuit condition. A circuit condition sets this DTC.
  3. 8:  This step is testing for an intermittent circuit condition. Thoroughly inspect the HO2S circuits for an intermittent circuit condition.
  4. 9:  This step is testing for an intermittent circuit condition. Thoroughly inspect the HO2S circuits for an intermittent circuit condition.
DTC P2196 HO2S Signal Biased Rich

Step Action Values Yes No
Schematic Reference:  Engine Controls Schematics 
Connector End View Reference:  Engine Control Module Connector End Views  or  Engine Controls Connector End Views 
1 Did you perform the Diagnostic System Check - Vehicle? - Go to Step 2  Go to Diagnostic System Check - Vehicle in Vehicle DTC Information
2 
  1. Allow the engine to reach operating temperature.
  2. Operate the vehicle within the parameters specified in Conditions for Running the DTC.
  3. Observe the diagnostic trouble code (DTC) information with a scan tool.
Did DTC P2196 fail this ignition?		 - Go to Step 4  Go to Step 3 
3
  1. Observe the Freeze Frame and/or the Failure records data for this DTC.
  2. Turn the ignition OFF for 30 seconds.
  3. Start the engine.
  4. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame and/or the Failure records data.
Does the DTC fail this ignition cycle?		 - Go to Step 4  Go to Diagnostic Aids
4 Is DTC P0137, P0138, or P0140 also set? - Go to Diagnostic Trouble Code (DTC) List - Vehicle in Vehicle DTC Information Go to Step 5 
5 
  1. Operate the engine above 1,200 RPM for 30 seconds.
  2. Observe the HO2S 2 voltage parameter with a scan tool.
Is the voltage less than the specified value?		 1,050 mV Go to Step 8  Go to Step 6 
6
  1. Turn OFF the ignition.
  2. Disconnect the heated oxygen sensor (HO2S) 2.
  3. Observe the HO2S 2 voltage parameter with a scan tool.
Is the voltage within the specified range?		 350-550 mV Go to Step 12  Go to Step 7 
7 Test the HO2S 2 signal circuit for a short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?		 - Go to Step 19  Go to Step 14 
8  Move the related HO2S 1 harnesses between the HO2S harness connector and the engine control module (ECM) while monitoring the HO2S 1 lambda parameter.
Does the HO2S parameter change abruptly while moving the related harnesses?		 - Go to Step 15  Go to Step 9 
9  Move the related HO2S 2 harnesses between the HO2S harness connector and the ECM while monitoring the appropriate HO2S voltage parameter.
Does the HO2S parameter change abruptly while moving the related harnesses?		 - Go to Step 15  Go to Step 10 
10
  1. Turn OFF the ignition.
  2. Disconnect the HO2S 1 and HO2S 2.
  3. Inspect the HO2S 1 and HO2S 2 for the following conditions:
    • For damaged wiring between the HO2S and the ECM-An intermittent circuit condition may cause this DTC to set.
    • For terminal corrosion or water intrusion in the HO2S harness connectors
    • For the correct terminal tension
    • The HO2S is securely installed.
    • For any exhaust leaks
  4. Repair as necessary. Refer to Wiring Repairs in Wiring Systems.
Did you find and correct the condition?		 - Go to Step 19  Go to Step 11 
11
  1. Disconnect the ECM.
  2. Test the HO2S 1 circuits for being shorted together between the HO2S connector and the ECM. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?		 - Go to Step 19  Go to Step 13 
12 Test for shorted terminals and for poor connections at the HO2S. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.
Did you find and correct the condition?		 - Go to Step 19  Go to Step 17 
13 Test for shorted terminals and for poor connections at the ECM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.
Did you find and correct the condition?		 - Go to Step 19  Go to Step 16 
14 Test for shorted terminals and for poor connections at the ECM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.
Did you find and correct the condition?		 - Go to Step 19  Go to Step 18 
15 Repair the circuit as necessary. Refer to Wiring Repairs in Wiring Systems.
Did you complete the repair?		 - Go to Step 19  -
16 Replace the HO2S 1. Refer to Heated Oxygen Sensor 1 Replacement .
Did you complete the replacement?		 - Go to Step 19  -
17 Replace the HO2S 2. Refer to Heated Oxygen Sensor 2 Replacement .
Did you complete the replacement?		 - Go to Step 19  -
18 Replace the ECM. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming.
Did you complete the replacement?		 - Go to Step 19  -
19
  1. Clear the DTCs with a scan tool.
  2. Turn OFF the ignition for 30 seconds.
  3. Start the engine.
  4. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records.
Did the DTC fail this ignition?		 - Go to Step 2  Go to Step 20 
20 Observe the Capture Info with a scan tool.
Are there any DTCs that have not been diagnosed?		 - Go to Diagnostic Trouble Code (DTC) List - Vehicle in Vehicle DTC Information System OK
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