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DTC P0101

DTC P0101

MAF sensor circuit range/performance problem

DETECTION CONDITION

The PCM compares the actual MAF amount with the expected MAF amount when the engine is running.

If the throttle opening angle is more than 50% and the MAF amount is less than 9 g/s {1.2 lb/min} (less than 1.4 V), the PCM determines that there is a MAF sensor circuit range/performance problem.
If the ECT is more than 70°C {158°F}, the engine speed is less than 2, 000 rpm and the MAF amount is more than 65 g/s {8.6 lb/min} (more than 2.8 V), the PCM determines that there is a MAF sensor circuit range/performance problem.

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.
PENDING CODE is available if the PCM detects the above malfunction condition during the first drive cycle.
FREEZE FRAME DATA (Mode 2/Mode 12) is available.
The DTC is stored in the PCM memory.

POSSIBLE CAUSE

MAF sensor malfunction
Eccentric shaft position sensor malfunction
PCM malfunction

DIAGNOSTIC PROCEDURE

STEP	INSPECTION		ACTION
1	VERIFY FREEZE FRAME DATA (MODE 12) HAS BEEN RECORDED Has the FREEZE FRAME DATA (Mode 12) been recorded?	Yes	Go to the next step.
1		No	Record the FREEZE FRAME DATA (Mode 12) 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 CURRENT INPUT SIGNAL STATUS Start the engine. Access the TP REL and MAF PIDs using the M-MDS. (See ON-BOARD DIAGNOSTIC TEST ). Read the MAF PID when the TP REL PID is more than 50 %. Is the MAF PID less than 9 g/s {1.2 lb/min}?	Yes	Verify that the TP REL PID changes smoothly while gradually opening throttle valve. If it changes smoothly, go to Step 5. If it does not change smoothly, replace the throttle body and go to Step 5. (See INTAKE-AIR SYSTEM REMOVAL/INSTALLATION ).
3		No	Go to the next step.
4	VERIFY CURRENT INPUT SIGNAL STATUS Start the engine. Access the ECT, RPM and MAF PIDs using the M-MDS. (See ON-BOARD DIAGNOSTIC TEST ). Warm-up the engine until the ECT PID is more than 70°C {158°F}. Read the MAF PID when the RPM PID is less than 2, 000 rpm. Is the MAF PID more than 65 g/s {8.6 lb/min}?	Yes	Go to Step 6.
4		No	Intermittent concern exists. Perform the "INTERMITTENT CONCERNS TROUBLESHOOTING". (See INTERMITTENT CONCERN TROUBLESHOOTING ).
5	VERIFY TROUBLESHOOTING OF DTC P0101 COMPLETED Make sure to reconnect all disconnected connectors. Clear the DTC from the PCM memory using the M-MDS. (See AFTER REPAIR PROCEDURE ). Start the engine. Access the TP REL PID using the M-MDS. (See ON-BOARD DIAGNOSTIC TEST ). Drive the vehicle for 5 s or more when the TP REL PID is more than 50 %. Perform the Pending Trouble Code Access Procedure. (See ON-BOARD DIAGNOSTIC TEST ). Is the PENDING CODE same as the DTC present?	Yes	Replace the PCM, then go to Step 9. (See PCM REMOVAL/INSTALLATION ).
5		No	Go to Step 9.
6	INSPECT MAF SENSOR Inspect the MAF sensor. (See MASS AIR FLOW (MAF) SENSOR INSPECTION ). Is there any malfunction?	Yes	Replace the MAF/IAT sensor, then go to Step 8. (See MASS AIR FLOW (MAF)/INTAKE AIR TEMPERATURE (IAT) SENSOR REMOVAL/INSTALLATION ).
6		No	Go to the next step.
7	INSPECT ECCENTRIC SHAFT POSITION SENSOR Inspect the eccentric shaft position sensor. (See ECCENTRIC SHAFT POSITION SENSOR INSPECTION ). Is there any malfunction?	Yes	Replace the eccentric shaft position sensor, then go to the next step. (See ECCENTRIC SHAFT POSITION SENSOR REMOVAL/INSTALLATION ).
7		No	Go to the next step.
8	VERIFY TROUBLESHOOTING OF DTC P0101 COMPLETED Make sure to reconnect a!! disconnected connectors. Clear the DTC from the PCM memory using the M-MDS. (See AFTER REPAIR PROCEDURE ). Start the engine. Access the ECT and RPM PIDs using the M-MDS. (See ON-BOARD DIAGNOSTIC TEST ). Warm-up the engine until the ECT PID is more than 70°C {158°F}. Drive the vehicle for 5 s or more when the RPM PID is less than 2, 000 rpm. Perform the Pending Trouble Code Access Procedure. (See ON-BOARD DIAGNOSTIC TEST ). Is the PENDING CODE same as the DTC present?	Yes	Replace the PCM, then go to the next step. (See PCM REMOVAL/INSTALLATION ).
8		No	Go to the next step.
9	VERIFY AFTER REPAIR PROCEDURE Perform the "AFTER REPAIR PROCEDURE ". (See AFTER REPAIR PROCEDURE ). Are any DTCs present?	Yes	Go to the applicable DTC inspection. (See DTC TABLE ).
9		No	DTC troubleshooting completed.