Test Description

WARNING: This page is about a different car, the 2007 Saturn Vue. However, it is still accessible from the selected car via links, so may be relevant.

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

4: This test must not be performed until the HO2S heater has cooled and stabilized for at least 15 minutes. Heater resistance is typically about 10 ohms at room temperature.
5: This step tests for high resistance in the ignition 1 voltage circuit of the HO2S 2. If the DMM does not display near battery voltage, repair the high resistance in the ignition 1 voltage circuit.

DTC P0141 or P0161

Step	Action	Values	Yes	No
Schematic Reference: Engine Controls Schematics Connector End View Reference: Powertrain 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
2	IMPORTANT: DTC P0141 is for bank 1 sensor 2 and DTC P0161 is for bank 2 sensor 2. Clear the DTCs with a scan tool. Start the engine. Observe the DTC info parameter with a scan tool for at least 30 seconds. Does the DTC fail this ignition?	-	Go to Step 4	Go to Step 3
3	Observe 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 4	Go to Intermittent Conditions
4	Turn OFF the ignition. Allow the heated oxygen sensor (HO2S) 2 to cool for at least 15 minutes. Disconnect the affected HO2S 2 connector. Measure the resistance from the heater control circuit of the HO2S 2, to the ignition 1 voltage circuit of the HO2S 2. Is the resistance within the specified range?	2-20 Ω	Go to Step 5	Go to Step 11
5	Turn ON the ignition. Connect a test lamp between the ignition 1 circuit of the HO2S and the powertrain control module (PCM) housing. Connect a DMM to the probe of the test lamp and the PCM housing. Refer to Measuring Voltage Drop . Does the voltage measure near the specified value?	B+	Go to Step 6	Go to Step 8
6	Disconnect the PCM connector containing the affected HO2S 2 heater control circuit. Measure the resistance between heater control circuit of the HO2S 2 and a good ground, with a DMM. Is the resistance within the specified range?	0-5 Ω	Go to Step 9	Go to Step 7
7	Repair the open or high resistance in the HO2S 2 heater control circuit. Refer to Wiring Repairs . Did you complete the repair?	-	Go to Step 12	-
8	Repair the open or high resistance in the HO2S 2 heater ignition 1 voltage circuit. Refer to Wiring Repairs . Did you complete the repair?	-	Go to Step 12	-
9	Test for intermittent and for a poor connection at the HO2S 2. Refer to Testing for Intermittent Conditions and Poor Connections and Wiring Repairs . Did you find and correct the condition?	-	Go to Step 12	Go to Step 10
10	Test for intermittent and for poor a connection at the PCM. Refer to Testing for Intermittent Conditions and Poor Connections and Wiring Repairs . Did you find and correct the condition?	-	Go to Step 12	Go to Step 11
11	Replace the HO2S. Refer to Heated Oxygen Sensor Replacement - Bank 1 Sensor 2 or Heated Oxygen Sensor Replacement - Bank 2 Sensor 2 . Did you complete the replacement?	-	Go to Step 12	-
12	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 2	Go to Step 13
13	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	System OK