Diagnostic Procedure

DTC P0139 DIAGNOSTIC PROCEDURE TABLE

STEP	INSPECTION		ACTION
1	VERIFY FREEZE FRAME DATA AND DIAGNOSTIC MONITORING TEST RESULTS HAVE BEEN RECORDED Have FREEZE FRAME DATA and DIAGNOSTIC MONITORING TEST RESULTS (HO2S related) been recorded?	Yes	Go to the next step.
1		No	Record the FREEZE FRAME DATA and DIAGNOSTIC MONITORING TEST RESULTS on the repair order, then go to the next step.
2	VERIFY RELATED REPAIR INFORMATION AVAILABILITY Verify related Service Bulletins and/or on-line repair information availability. Is any related repair information available?	Yes	Perform repair or diagnosis according to the available repair information. If the vehicle is not repaired, go to the next step.
2		No	Go to the next step.
3	VERIFY RELATED PENDING AND STORED DTC Turn the ignition switch off, then to the ON position (Engine off). Verify pending and/or stored DTCs using the WDS or equivalent. Is DTC P0443 also present?	Yes	Go to DTC P0443 troubleshooting procedures, then go to Step 13.
3		No	Go to the next step.
4	IDENTIFY TRIGGER DTC FOR FREEZE FRAME DATA Is DTC P0139 on FREEZE FRAME DATA?	Yes	Go to the next step.
4		No	Go to troubleshooting procedures for DTC on OBD-II FREEZE FRAME DATA . (See DTC TABLE .)
5	VERIFY CURRENT INPUT SIGNAL STATUS Warm up the engine. Access O2S12 PID using WDS or equivalent. Inspect PID under following accelerator pedal conditions in PARK (AT) or NEUTRAL (MT). Is PID normal? More than 0.55 V when suddenly depress accelerator pedal (rich condition). Less than 0.55 V just after release of accelerator pedal (lean condition).	Yes	Go to Step 8.
5		No	Go to the next step.
6	INSPECT INSTALLATION OF REAR HO2S Inspect if the rear HO2S is loosely installed. Is the sensor installed securely?	Yes	Go to the next step.
6		No	Retighten the sensor, then go to Step 13.
7	INSPECT GAS LEAKAGE FROM EXHAUST SYSTEM Visually inspect if there is any gas leakage is found between the exhaust manifold and rear HO2S. Is there gas leakage?	Yes	Repair or replace malfunctioning faulty exhaust part, then go to Step 13.
7		No	Replace sensor, then go to Step 13.
8	INSPECT LONG TERM FUEL TRIM Access LONGFT1 PIDs Compare it with FREEZE FRAME DATA recorded at Step 1. Is it below FFD value?	Yes	Engine is driven under rich condition. Go to the next step.
8		No	Engine is driven under lean condition. Go to Step 10.
9	INSPECT FUEL LINE PRESSURE (Excessive fuel line pressure) Turn the ignition switch off. Inspect fuel line pressure while the engine running. (See FUEL LINE PRESSURE INSPECTION .) Is the fuel line pressure normal?	Yes	Go to Step 12.
9		No	Inspect fuel pump maximum pressure and fuel return pipe for clogging. (See FUEL PUMP UNIT INSPECTION .) If there is any problem, repair or replace the parts. If all items above are normal, replace fuel pump unit. (See FUEL PUMP UNIT REMOVAL/INSTALLATION .) Then go to Step 13.
10	INSPECT FUEL LINE PRESSURE (Low fuel line pressure) Turn the ignition switch off. Inspect fuel line pressure while the engine running. (See FUEL LINE PRESSURE INSPECTION .) Is fuel line pressure normal?	Yes	Go to Step 12.
10		No	Go to the next step.
11	INSPECT FUEL LINE FROM FUEL PUMP TO FUEL DELIVERY PIPE Visually inspect the fuel line for any leakage. Is there fuel leakage?	Yes	Replace the fuel line, then go to Step 13.
11		No	Inspect the fuel filters for the following: Foreign materials or stain inside fuel filter (low-pressure side) Perform the following actions according to the result. If foreign material or stain is found inside fuel filter (low-pressure side), clean the fuel tank and filter. If normal, replace fuel pump unit. (See FUEL PUMP UNIT REMOVAL/INSTALLATION .) Then go to Step 13.
12	INSPECT SEALING OF ENGINE COOLANT PASSAGE Perform "ENGINE COOLANT LEAKAGE INSPECTION." (See ENGINE COOLANT LEAKAGE INSPECTION .) Is there any malfunction?	Yes	Go to the next step.
12		No	Repair or replace the malfunctioning part according to inspection results. Then go to the next step.
13	VERIFY TROUBLESHOOTING OF DTC P0139 COMPLETED Make sure to reconnect all disconnected connectors. Turn the ignition switch to the ON position. (Engine off) Clear the DTC from the memory using WDS or equivalent. Perform the "PCM Adaptive Memory Produce Drive Mode" and "HO2S heater, HO2S, and TWC Repair Verification Drive Mode". (See OBD-II DRIVE MODE .) Is the PENDING CODE for this DTC present?	Yes	Replace the PCM, then go to the next step. (See PCM REMOVAL/INSTALLATION .)
13		No	Go to the next step.
14	VERIFY AFTER REPAIR PROCEDURE Perform the "AFTER REPAIR PROCEDURE". (See AFTER REPAIR PROCEDURE .) Are any DTC present?	Yes	Go to the applicable DTC troubleshooting. (See DTC TABLE .)
14		No	Troubleshooting completed.