Diagnostic procedure

DTC P2178 [L3] DIAGNOSTIC PROCEDURE

STEP	INSPECTION		ACTION
1	IDENTIFY TRIGGER DTC FOR FREEZE FRAME DATA (MODE 2) Is DTC P2178 on FREEZE FRAME DATA (Mode 2)?	Yes	Go to the next step.
1		No	Go to troubleshooting for DTC on FREEZE FRAME DATA (Mode 2). (See DTC TABLE .)
2	VERIFY FREEZE FRAME DATA (MODE 12) HAVE BEEN RECORDED Have FREEZE FRAME DATA (Mode 12) been recorded?	Yes	Go to the next step.
2		No	Record the FREEZE FRAME DATA (Mode 12) on the repair order, then go to the next step.
3	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.
3		No	Go to the next step.
4	VERIFY RELATED PENDING CODE OR STORED DTCS Turn the ignition switch off, then to the ON position (Engine off). Verify related pending code or stored DTCs. Is other DTC present?	Yes	If misfire DTC is present, go to Step 8. If other DTC is present, go to applicable DTC inspection. (See DTC TABLE .)
4		No	If drive ability concern is present, go to Step 8. If not, go to the next step.
5	VERIFY CURRENT INPUT SIGNAL STATUS (IGNITION SWITCH TO THE ON POSITION/IDLE) Access PCM PIDs APP1, APP2, ECT, MAF, TP REL and VSS using M-MDS. Is there any signal that is far out of specification when the ignition switch is at the ON position and the engine runs?	Yes	Inspect the suspected circuit. If the inspection results are normal: Go to the next step. If the inspection results are not normal: Repair or replace the malfunctioning part according to the inspection results, then go to Step 21.
5		No	Go to the next step.
6	VERIFY CURRENT INPUT SIGNAL STATUS UNDER TROUBLE CONDITION CAUTION: While performing this step, always operate the vehicle in a safe and lawful manner. When the M-MDS is used to observe monitor system status while driving, be sure to have another technician with you, or record the data in the M-MDS using the PID/DATA MONITOR AND RECORD capturing function and inspect later. Inspect the same PIDs as Step 5 while simulating FREEZE FRAME DATA (Mode 2) condition. Is there any signal which causes drastic changes?	Yes	Inspect the suspected circuit. If the inspection results are normal: Go to the next step. If the inspection results are not normal: Repair or replace the malfunctioning part according to the inspection results, then go to Step 21.
6		No	Go to the next step.
7	INSPECT A/F SENSOR HEATER Inspect the A/F sensor heater. (See AIR FUEL RATIO (A/F) SENSOR INSPECTION .) Is there any malfunction?	Yes	Go to the next step.
7		No	Replace the A/F sensor, then go to Step 21. (See EXHAUST SYSTEM REMOVAL/INSTALLATION .)
8	VERIFY CURRENT INPUT SIGNAL STATUS OF A/F SENSOR Inspect the A/F sensor. (See AIR FUEL RATIO (A/F) SENSOR INSPECTION .) Is there any malfunction?	Yes	Go to the next step.
8		No	Go to Step 11.
9	INSPECT INSTALLATION OF A/F SENSOR Inspect if the A/F sensor is loosely installed. Is the A/F sensor installed securely?	Yes	Go to the next step.
9		No	Retighten the A/F sensor, then go to Step 21. (See EXHAUST SYSTEM REMOVAL/INSTALLATION .)
10	INSPECT EXHAUST GAS LEAKAGE Visually inspect for the exhaust gas leakage between exhaust manifold and A/F sensor. Is there any malfunction?	Yes	Repair or replace the malfunctioning part according to the inspection results, then go to Step 21.
10		No	Replace the A/F sensor, then go to Step 21. (See AIR FUEL RATIO (A/F) SENSOR, HEATED OXYGEN SENSOR (HO2S) REMOVAL/INSTALLATION .)
11	VERIFY CURRENT INPUT SIGNAL STATUS OF MAF SENSOR Connect the M-MDS to the DLC-2 Start the engine. Access the PCM PID MAF using the M-MDS. Verify that the MAF PID changes quickly according to engine speed. Is the PID normal?	Yes	Go to the next step.
11		No	Replace the MAF/IAT sensor, then go to Step 21.
12	INSPECT PURGE SOLENOID OPERATION Perform Purge Control System Inspection. (See ENGINE CONTROL SYSTEM OPERATION INSPECTION .) Does purge control system work properly?	Yes	Go to the next step.
12		No	Repair or replace the malfunctioning part according to inspection result, then go to Step 21.
13	INSPECT EGR VALVE OPERATION Perform EGR Control System Inspection. (See ENGINE CONTROL SYSTEM OPERATION INSPECTION .) Does the EGR control system work properly?	Yes	Go to the next step.
13		No	Repair or replace the malfunctioning part according to inspection result, then go to Step 21.
14	INSPECT VARIABLE TUMBLE CONTROL OPERATION Perform Variable Tumble Control Operation Inspection. (See ENGINE CONTROL SYSTEM OPERATION INSPECTION .) Does the variable tumble control work properly?	Yes	Go to the next step.
14		No	Repair or replace the malfunctioning part according to inspection result, then go to Step 21.
15	INSPECT VARIABLE VALVE TIMING CONTROL SYSTEM OPERATION Inspect variable valve timing control system operation. (See ENGINE CONTROL SYSTEM OPERATION INSPECTION .) Does variable valve timing control system work properly?	Yes	Go to the next step.
15		No	Repair or replace the malfunctioning part according to inspection results, then go to Step 21.
16	INSPECT FUEL LINE PRESSURE Turn the ignition switch off. Inspect the fuel line pressure. (See FUEL LINE PRESSURE INSPECTION .) Is the fuel line pressure normal?	Yes	Go to Step 18.
16		No	If the fuel pressure is too high, replace fuel pump unit, then go to Step 21. If the fuel line pressure is low, go to the next step.
17	INSPECT FUEL LINE FROM FUEL PUMP TO FUEL DISTRIBUTOR Visually inspect the fuel line for any leakage. Is fuel leakage found?	Yes	Replace suspected fuel line, then go to Step 21.
17		No	Inspect for foreign materials or stain inside fuel filter (low-pressure). If for foreign materials or stain inside fuel filter (low-pressure), clean off the fuel tank and filter. Then go to Step 21.
18	INSPECT IGNITION SYSTEM Perform the spark test. (See ENGINE CONTROL SYSTEM OPERATION INSPECTION .) Is strong blue spark visible at each cylinder?	Yes	Go to the next step,
18		No	Repair or replace the malfunctioning part according to spark test result, then go to Step 21.
19	INSPECT FUEL INJECTOR OPERATION Perform the Fuel Injector Operation Inspection. (See ENGINE CONTROL SYSTEM OPERATION INSPECTION .) Do the fuel injectors operate properly?	Yes	Go to the next step.
19		No	Repair or replace the malfunctioning part according to inspection results, then go to Step 21.
20	INSPECT PCV VALVE OPERATION Inspect the PCV valve operation. (See POSITIVE CRANKCASE VENTILATION (PCV) VALVE INSPECTION .) Is the PCV valve normal?	Yes	Go to the next step.
20		No	Replace the PCV valve, then go to the next step.
21	VERIFY TROUBLESHOOTING OF DTC P2178 COMPLETED Make sure to reconnect all disconnected connectors. Clear the DTC from the PCM memory using the M-MDS. (See AFTER REPAIR PROCEDURE .) Perform the KOER self test. (See KOEO/KOER SELF TEST .) Is the PENDING CODE for this DTC present?	Yes	Replace the PCM, then go to the next step. (See PCM REMOVAL/INSTALLATION .)
21		No	Go to the next step.
22	VERIFY AFTER REPAIR PROCEDURE Perform "AFTER REPAIR PROCEDURE". (See AFTER REPAIR PROCEDURE .) Is there any DTC present?	Yes	Go to the applicable DTC inspection. (See DTC TABLE .)
22		No	Troubleshooting completed.