Diagnostic Aids

WARNING: This page is about a different variant/trim than selected.

The following table illustrates the ECM connector locations:

DTC P0137

ECM Connector Location
C2	C1
Front of Vehicle

Use the J 35616 Connector Test Adapter Kit for any test that requires probing the ECM harness connector or a component harness connector. See Special Tools .
The rear HO2S will not go into closed loop when the engine is idling. Once the HO2S are at operating temperature, and the vehicle is moving, the rear HO2S will go into closed loop.
For an intermittent condition, refer to Intermittent Conditions .

DTC P0137

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	IMPORTANT: Inspect the heated oxygen sensor (HO2S) for being secure before proceeding with this DTC. A sensor that is loose could cause this DTC to set. Allow the engine to reach operating temperature. Operate the engine above 1,200 RPM for 30 seconds. Observe the HO2S 2 voltage parameter with a scan tool. Is the voltage less than the specified value?	60 mV	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 Diagnostic Aids
4	Turn OFF the ignition. Disconnect the HO2S. Turn ON the ignition, with the engine OFF. Observe the HO2S voltage parameter with a scan tool. Is the HO2S voltage within the specified range?	375-575 mV	Go to Step 6	Go to Step 5
5	Turn OFF the ignition. Disconnect the engine control module (ECM) connector. Test the HO2S signal circuit for a short to ground. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition?	-	Go to Step 9	Go to Step 8
6	Test or inspect for the following conditions: For an injector that is too lean-Refer to Fuel Injector Balance Test with Special Tool . For a fuel system that is contaminated-Refer to Alcohol/Contaminants-in-Fuel Diagnosis (w/o Special Tool) or Alcohol/Contaminants-in-Fuel Diagnosis (w/Special Tool) . For a fuel pressure that is too low-Refer to Fuel System Diagnosis . For an exhaust leak near the HO2S-Refer to Symptoms - Engine Exhaust in Engine Exhaust. For a vacuum or crankcase leak Did you find and correct the condition?	-	Go to Step 9	Go to Step 7
7	Replace the HO2S. Refer to Heated Oxygen Sensor 2 Replacement . Did you complete the replacement?	-	Go to Step 9	-
8	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 9	-
9	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 10
10	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