DTC P0401[ZJ, ZY, Z6]

id0102c1815300

With Throttle Valve Actuator Only

DTC P0401

EGR flow insufficient detected

DETECTION CONDITION

•  If the fluctuation in intake manifold pressure (3 times average value) is too low when the EGR value opens/closes.

Diagnostic support note

•  This is a continuous monitor (EGR).

•  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 PCM detects the above malfunction condition.

•  The FREEZE FRAME DATA is available.

•  The DTC is stored in the PCM memory.

POSSIBLE CAUSE

•  EGR valve is stuck.

•  MAP sensor malfunction

•  Vacuum hose is poorly connection.

•  PCM malfunction

DTC P0401	EGR flow insufficient detected
DETECTION CONDITION	• If the fluctuation in intake manifold pressure (3 times average value) is too low when the EGR value opens/closes. Diagnostic support note • This is a continuous monitor (EGR). • 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 PCM detects the above malfunction condition. • The FREEZE FRAME DATA is available. • The DTC is stored in the PCM memory.
POSSIBLE CAUSE	• EGR valve is stuck. • MAP sensor malfunction • Vacuum hose is poorly connection. • PCM malfunction

Diagnostic procedure

STEP	INSPECTION		ACTION
1	VERIFY FREEZE FRAME DATA HAS BEEN RECORDED • Has FREEZE FRAME DATA been recorded?	Yes	Go to the next step.
1		No	Record the FREEZE FRAME DATA on the repair order, then go to the next step.
2	VERIFY RELATED SERVICE INFORMATION AVAILABILITY • Verify related Service Information availability. • Is any related Service Information available?	Yes	Perform repair or diagnosis according to the available Service Information. • If the vehicle is not repaired, go to the next step.
2		No	Go to the next step.
3	INSPECT VACUUM HOSE • Verify that there is no malfunction such as clogging or leakage in the vacuum hose between the manifold absolute pressure sensor and the intake manifold. • Is there any malfunction?	Yes	Repair or replace the vacuum hose, then go to Step 7.
3		No	Go to the next step.
4	INSPECT EGR VALVE • Inspect the EGR valve. (See EGR VALVE INSPECTION[ZJ, ZY, Z6].) • Is there any malfunction?	Yes	Replace the EGR valve, then go to Step 7. (See EGR VALVE REMOVAL/INSTALLATION[ZJ, ZY, Z6].)
4		No	Go to the next step.
5	INSPECT MAP SENSOR • Inspect the MAP sensor. (See MANIFOLD ABSOLUTE PRESSURE (MAP) SENSOR INSPECTION[ZJ, ZY, Z6].) • Is there any malfunction?	Yes	Replace the MAP sensor, then go to Step 7.
5		No	Go to the next step.
6	INSPECT EGR ROUTING • Remove the EGR valve. (See EGR VALVE REMOVAL/INSTALLATION[ZJ, ZY, Z6].) • Verify that the EGR valve gasket installation is correct. • Verify that there is no sticking in the EGR valve and no clogging of the EGR routing. • Is there any malfunction?	Yes	Replace the malfunctioning part, then go to Step 7.
6		No	Go to the next step.
7	VERIFY TROUBLESHOOTING OF DTC P0401 COMPLETED • Make sure to reconnect all disconnected connectors. • Clear the DTC from the PCM memory using the M-MDS. • Perform the KOER self-test. (See KOEO/KOER SELF TEST[ZJ, ZY, Z6].) • Is the PENDING CODE for this DTC present?	Yes	Replace the PCM, then go to the next step. (See PCM REMOVAL/INSTALLATION[ZJ, ZY, Z6].)
7		No	Go to the next step.
8	VERIFY AFTER REPAIR PROCEDURE • Perform the “AFTER REPAIR PROCEDURE”. (See AFTER REPAIR PROCEDURE[ZJ, ZY, Z6].) • Are any DTCs present?	Yes	Go to the applicable DTC inspection. (See DTC TABLE[ZJ, ZY, Z6].)
8		No	DTC troubleshooting completed.