DTC P0131, P0132


DTC P0131 DTC P0132	HO2S stuck low HO2S stuck high
DETECTION CONDITION	• The PCM monitors the input voltage from the HO2S when the following monitoring conditions are met. If the input voltage from sensor remains 0.45 V or more/or less for 46 s or more, the PCM determines that there is no HO2S inversion. MONITORING CONDITIONS - Engine speed is 1,500 rpm or more. - Engine coolant temperature is 80 °C {176°F} or more. - Within feedback range Diagnostic support note • This is a continuous monitor (CCM). • The MIL illuminates if the PCM detects the above malfunction condition in two consecutive drive cycles or in one drive cycle while the DTC for the same malfunction has been stored in the PCM. • The PENDING CODE is available if the PCM detects the above malfunction condition during first drive cycle. • The FREEZE FRAME DATA is available. • The DTC is stored in the PCM memory.
POSSIBLE CAUSE	• HO2S malfunction • HO2S heater malfunction • Fuel injector malfunction • Pressure regulator malfunction • Fuel pump malfunction • Fuel delivery hose clogging or leakage • Fuel filter clogging • Fuel return hose clogging or leakage • Air suction or leakage • PCV valve malfunction • Purge solenoid valve malfunction • Purge solenoid hoses are hooked up incorrectly. • Ignition coil malfunction • Insufficient compression • Engine malfunction


STEP	INSPECTION		ACTION
1	VERIFY FREEZE FRAME DATA HAS BEEN RECORDED • Has the FREEZE FRAME DATA been recorded?	Yes	Go to the next step.
1		No	Record the FREEZE FRAME DATA on repair order, then go to the next step.
2	VERIFY RELATED SERVICE INFORMATION AVAILABILITY • Check for related Service Information availability. • Is any related Service Information available?	Yes	Perform the repair or diagnosis according to available Service 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 DTCs • Turn the ignition switch off, then start the engine. • Verify the pending and stored DTCs using the WDS or equivalent. • Are any other DTCs present?	Yes	Go to the appropriate DTC troubleshooting procedures.
3		No	Go to the next step.
4	IDENTIFY TRIGGER DTC FOR FREEZE FRAME DATA • Is DTC P0131 and P0132 displayed in the FREEZE FRAME DATA?	Yes	Go to the next step.
4		No	Go to the troubleshooting procedures for the DTC displayed in the FREEZE FRAME DATA.
5	VERIFY CURRENT INPUT SIGNAL STATUS - IS CONCERN INTERMITTENT OR CONSTANT • Warm up the engine. • Access the O2S11 for P0131 and P0132 PID using the WDS or equivalent. • Verify the PID while racing the engine (in PARK (ATX) or NEUTRAL (MTX)). • Is the PID reading normal? - More than 0.45 V when suddenly depressing accelerator pedal (rich condition) - Less than 0.45 V just after releasing accelerator pedal (lean condition)	Yes	Go to the next step.
5		No	Replace the HO2S, then go to Step 19.
6	INSPECT LONG TERM FUEL TRIM • Access the LONGFT1 for P0131 and P0132 PID using the WDS or equivalent. • Compare it with the FREEZE FRAME DATA recorded at Step1. • Did it decrease?	Yes	The Engine is driven under rich condition. Go to the next step.
6		No	The Engine is driven under lean condition. Go to step 9.
7	INSPECT FUEL LINE PRESSURE (EXCESSIVE FUEL LINE PRESSURE) • Turn the ignition switch off. • Inspect fuel line pressure. (See FUEL LINE PRESSURE INSPECTION.) • Is fuel line pressure normal?	Yes	Go to the next step.
7		No	Inspect the following parts and repair or replace if necessary: • Fuel pump maximum pressure. • Fuel return pipe for clogging. - If all items above are normal, replace the pressure regulator. Then go to Step 19.
8	INSPECT IF PURGE SOLENOID IS STUCK OPEN • Turn the ignition switch off. • Disconnect both hoses from the purge solenoid valve. • Blow air through the purge solenoid valve. • Can air be blown through the valve?	Yes	Replace the purge solenoid valve.
8		No	Go to Step 13.
9	INSPECT PCV VALVE OPERATION • Inspect the PCV valve operation. (See PCV VALVE INSPECTION.) • Is the PCV valve normal?	Yes	Go to the next step.
9		No	Replace the PCV, then go to Step 19.
10	INSPECT FUEL LINE PRESSURE (LOW FUEL LINE PRESSURE) • Turn the ignition switch off. • Inspect fuel line pressure. (See FUEL LINE PRESSURE INSPECTION.) • Is fuel line pressure normal?	Yes	Go to step 13.
10		No	Go to the next step.
11	INSPECT FUEL PUMP MAXIMUM PRESSURE • Stop the engine. • Turn the ignition switch to the ON position (Engine off). • Perform the fuel pump maximum pressure inspection. (See FUEL LINE PRESSURE INSPECTION.) • Is the fuel pump maximum pressure normal?	Yes	Go to the next step.
11		No	Inspect the fuel pump circuit for an open circuit or poor connection. • Repair or replace the suspected circuit. • If the circuit is normal, replace the fuel pump, then go to Step 19.
12	INSPECT FUEL LINE FROM FUEL PUMP TO FUEL DELIVERY PUMP • Visually inspect fuel line for any leakage. • Is any fuel leakage found?	Yes	Replace the suspected fuel line, then go to Step 19.
12		No	Inspect the fuel filters for the following: • Restriction or clogging at the fuel filter (high-pressure). • Foreign material or staining inside the fuel filter (low-pressure) - If restriction or clogging is found at the fuel filter (high-pressure), replace the fuel filter. - If foreign materials or stain is found inside the fuel filter (low-pressure), clean the fuel tank and the filter. - If all items above are normal, replace the pressure regulator. Then go to Step 19.
13	CHECK IGNITION COIL OPERATION • Perform the spark test. (See Spark Test, Spark Test.) • Do all cylinders show a blinking condition?	Yes	Go to step 16.
13		No	Go to the next step.
14	INSPECT POWER SUPPLY TERMINAL AT IGNITION COIL CONNECTOR • Disconnect the ignition coil connector. • Turn the ignition switch to the ON position (Engine off). • Measure the voltage between ignition coil connector terminal D (wiring harness-side) and body ground. • Is the voltage B+?	Yes	Go to the next step.
14		No	Check for an open circuit between the ignition coil connector and the ignition switch. Repair or replace the wiring harness, then go to Step 19.
15	INSPECT IGNITION COIL RESISTANCE • Check the ignition coil resistance. (See IGNITION COIL INSPECTION [ZJ, ZY].) • Is the coil resistance normal?	Yes	Go to the next step.
15		No	Replace the ignition coil, then go to Step 19.
16	INSPECT ENGINE COMPRESSION • Inspect the engine compression. (See COMPRESSION INSPECTION [ZJ, ZY].) • Is it normal?	Yes	Go to the next step.
16		No	Implement engine overhaul for repairs, then go to the next step.
17	INSPECT FUEL INJECTOR OPERATION • Turn the ignition switch off. • Inspect the injector. (See FUEL INJECTOR INSPECTION.) • Is the injector normal?	Yes	Go to the next step.
17		No	Replace the injector, then go to Step 19.
18	INSPECT SEALING OF ENGINE COOLANT PASSAGE Warning • Removing the radiator cap when the radiator is hot is dangerous. Scalding coolant and steam may shoot out and cause serious injury. • When removing the radiator cap, wrap a thick cloth around it and turn it slowly. • Remove the radiator cap. • Implement the procedure to bleed air from the engine coolant, then run the engine at idle. • Are there small bubbles, that makes the engine coolant white at the filling opening? Note • Large bubbles are normal since they are due to remaining air coming out from the engine coolant passage.	Yes	Air penetrates due to poor sealing to head gasket or other areas between the combustion chamber and the engine coolant passage. Repair or replace the malfunctioning parts, then go to the next step.
18		No	Go to the next step.
19	VERIFY TROUBLESHOOTING OF DTC P0131 or P0132 COMPLETED • Make sure to reconnect all disconnected connectors. • Turn the ignition switch to the ON position (Engine off). • Clear the DTC from the PCM memory using WDS or equivalent. • Start the engine. • Access the ECT and RPM PIDs using WDS or equivalent. • Make sure that the ECT PID is 80 °C {176 °F} or more. • Increase and keep the engine speed at 1,500 rpm or more for at least 1 min. • Is PENDING CODE same as DTC present?	Yes	Replace the PCM, then go to the next step. (See PCM REMOVAL/INSTALLATION.)
19		No	Go to the next step.
20	VERIFY AFTER REPAIR PROCEDURE • Perform the "AFTER REPAIR PROCEDURE". (See AFTER REPAIR PROCEDURE.) • Are any DTCs present?	Yes	Go to the applicable DTC troubleshooting. (See DTC TABLE.)
20		No	Troubleshooting completed.