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Home >> Buick >> 2006 >> Allure CXS >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - 3.6L (Ly7) - DTC P0135 To DTC P0430 >> DTC P0141 >> Test Description

Test Description

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

  1. 2:  This step determines if the condition exists.
  2. 4:  This step tests the signal circuit of the HO2S for high resistance.
DTC P0141

Step Action Values Yes No
Schematic Reference:  Engine Controls Schematics 
Connector End View Reference:  Engine Control Module (ECM) 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 P0141 fail this ignition?		 - Go to Step 4  Go to Step 3 
3
  1. Observe the Freeze Frame/Failure Records for this DTC.
  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 4  Go to Diagnostic Aids
4 
  1. Turn OFF the ignition.
  2. Disconnect the heated oxygen sensor (HO2S).
  3. Connect a 3-amp fused jumper wire between the signal circuit of the HO2S and a good ground.
  4. Turn ON the ignition, with the engine OFF.
  5. Observe the HO2S voltage parameter with a scan tool.
Is the voltage less than the specified value?		 25 mV Go to Step 5  Go to Step 8 
5
  1. Connect a 3-amp fused jumper wire between the signal circuit and the low reference circuit of the HO2S.
  2. Observe the HO2S voltage parameter with a scan tool.
Is the voltage less than the specified value?		 25 mV Go to Step 6  Go to Step 9 
6
    IMPORTANT: Use the J 35616-200  Test Lamp Kit for this test. If the J 35616-200  is not available, use a test lamp that measures more than 20 ohms.
  1. Connect a test lamp between the ignition 1 voltage circuit of the HO2S and a good ground.
  2. Measure the voltage between the probe of the test lamp and a good ground with a DMM. Refer to Measuring Voltage Drop in Wiring Systems.
Is the voltage at the specified value?		 B+ Go to Step 7  Go to Step 12 
7
  1. Disconnect the engine control module (ECM).
  2. Measure the resistance of the heater control circuit of the HO2S, with a DMM.
Is the resistance less than the specified value?		 5 Ω Go to Step 10  Go to Step 13 
8 Test the signal circuit of the HO2S for an open or for high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?		 - Go to Step 16  Go to Step 11 
9 Test the low reference circuit of the HO2S for an open or for high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?		 - Go to Step 16  Go to Step 11 
10 Test for shorted terminals and 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 16  Go to Step 14 
11 Test for shorted terminals and 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 16  Go to Step 15 
12 Repair the open or the high resistance in the ignition 1 voltage circuit of the HO2S heater. Refer to Wiring Repairs in Wiring Systems.
Did you complete the repair?		 - Go to Step 16  -
13 Repair the open or the high resistance in the heater control circuit of the HO2S. Refer to Wiring Repairs in Wiring Systems.
Did you complete the repair?		 - Go to Step 16  -
14 Replace the HO2S. Refer to Heated Oxygen Sensor Replacement - Position 2 .
Did you complete the replacement?		 - Go to Step 16  -
15 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 16  -
16
  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 17 
17 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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