DTC P0130: Front Ho2S Circuit Range/Performance Problem - Forester, IMPREZA 2.5L & Legacy & Outback 2.5L A/T

Perform basic diagnostic procedure. See BASIC DIAGNOSTIC PROCEDURE . If DTC P0131, P0132, P0133, P1130, P1131, P1132, P1133 and/or P1137 exist, diagnose and repair those DTCs. If only DTC P0130 exists, go to next step.
Start engine and warm to more than 160°F (70°C). Operate engine at idle for one minute. Using scan tool, observe front HO2S signal. If voltage is .85-1.15 volt at idle, go to next step. If voltage is not .85-1.15 volt at idle, go to step 4.
Slowly accelerate engine (five seconds) from idle to 5,000 RPM a total of 5 times. If voltage is more than 1.1 volt for more than a moment, go to step 6. If voltage is not more than 1.1 volt for more than a moment, go to next step.

Turn ignition off. Disconnect front HO2S connector and ECM connector B136 (30-pin connector). Measure resistance between ECM terminals and HO2S connector terminals. See ECM-TO-FRONT HO2S CONNECTOR IDENTIFICATION - FORESTER, IMPREZA 2.5L & LEGACY & OUTBACK 2.5L A/T table. See Figure and Figure . If resistance is less than 5 ohms, go to next step. If resistance is not less than 5 ohms, locate and repair open circuit in wiring and check for poor terminal contact in connectors between ECM and front HO2S. See WIRING DIAGRAMS article.

ECM-TO-FRONT HO2S CONNECTOR IDENTIFICATION - FORESTER, IMPREZA 2.5L & LEGACY & OUTBACK 2.5L A/T

ECM B136 (30-Pin Connector) Terminal No.	Front HO2S Connector Terminal No.
6	1
7	6
19	3
20	4

With DVOM connected to ground, measure resistance between ECM connector B136 (30-pin connector) terminals No. 6, 7, 19 and 20. If resistance is more than 1 megohm, go to next step. If resistance is not more than 1 megohm, locate and repair short to ground in wiring between front HO2S and ECM.
Check for faulty exhaust system components, cracks and/or leaks. Check electrical connectors between front HO2S sensor and ECM. Repair and/or replace components as necessary. If exhaust system is okay, replace front HO2S. Clear memory and perform verification procedure. See CLEARING DIAGNOSTIC TROUBLE CODES and VERIFICATION PROCEDURE .