DTC P20E9:71 [MZR-CD 2.2]


id0102f3166900

DTC P20E9:71

Urea pump pressure too high

DETECTION CONDITION
•  The SCR control unit monitors urea pump pressure sensor using the urea pump pressure sensor while the urea injection control is operating. If the urea pump pressure is above 580 kPa {5.91 kgf/cm2, 84.1 psi} for 60 sec., the SCR control unit determines that the urea pump pressure is high.
Diagnostic support note
•  The MIL illuminates if the SCR control unit detects the above malfunction condition in first drive cycle.
•  The SCR warning light flashes if the SCR control unit detects the above malfunction condition in first drive cycle.
•  PENDING CODE is available if the SCR control unit detects the above malfunction condition during the first drive cycle.
•  FREEZE FRAME DATA (mode2) and snapshot data are available.
•  The DTC is stored in the SCR control unit memory.
POSSIBLE CAUSE
•  Urea pump malfunction (Excessive feed)
•  Urea pump pressure sensor malfunction (specific malfunction)
•  Open or short circuit in wiring harness between urea pump pressure sensor and SCR control unit
•  Restrict or clogged in urea pump return line
•  Restrict or clogged in urea return line orifice (in urea tank)
•  SCR control unit malfunction

Diagnostic procedure

STEP

INSPECTION

ACTION

1
VERIFY FREEZE FRAME DATA AND DIAGNOSTIC MONITORING TEST RESULTS HAS BEEN RECORDED
•  Have FREEZE FRAME DATA (mode2) or snapshot data been recorded?
Yes
Go to the next step.
No
Record the FREEZE FRAME DATA (mode2) and snapshot 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 the repair or diagnosis according to the available Service Information.
•  If the vehicle is not repaired, go to the next step.
No
Go to the next step.
3
IDENTIFY TRIGGER DTC FOR FREEZE FRAME DATA (MODE2)
•  Is DTC P20E9:71 on FREEZE FRAME DATA (mode2)?
Yes
Go to the next step.
No
Go to troubleshooting for DTC on FREEZE FRAME DATA (mode2).
4
VERIFY RELATED PENDING CODE OR STORED DTC
•  Switch the ignition to off, then ON (Engine off).
•  Verify the PENDING CODE or stored DTCs using the M-MDS.
•  Is the DTC P20E0:00 or P20E9:73 also present?
Yes
Go to the appropriate DTC troubleshooting procedures.
No
Go to the next step.
5
INSPECT WHETHER MALFUNCTION IS IN UREA PUMP OR ELSEWHERE
•  Perform urea pump inspection using the M-MDS.
•  Is the inspection result normal?
Yes
Go to the next step.
No
Repair or replace malfunctioning part according to inspection result, then go to Step 8.
6
INSPECT WHETHER MALFUNCTION IS IN UREA PUMP PRESSURE SENSOR OR ELSEWHERE
•  Access the SCR control unit PID LINE_PRESS using the M-MDS.
•  Start the engine and warm it up to normal operating temperature.
•  Stop the engine.
•  Switch the ignition ON (Engine off).
•  Monitor the PID LINE_PRESS.
•  Is the monitoring value approx. 0 Pa?
Yes
Go to the next step.
No
Inspect the wiring harness between urea pump pressure sensor and SCR control unit for open and/or short.
•  If the open or short circuit is detected, repair or replace malfunctioning part.
•  If the wiring harnesses are normal, replace the urea pump.
(Urea pump pressure sensor-specific malfunction)
Then go to Step 8.
7
INSPECT WHETHER MALFUNCTION IS IN UREA HOSE OR UREA PUMP RETURN LINE
•  Perform urea pump inspection without urea hose using the M-MDS.
•  Is the inspection result normal?
Yes
Go to the next step.
No
Replace the urea pump, then go to the next step.
(Urea pump return line or return line orifice (in urea tank) clogging)
8
VERIFY TROUBLESHOOTING OF DTC P20E9:71 COMPLETED
•  Make sure to reconnect all disconnected connectors.
•  Clear the DTC from the SCR control unit memory using the M-MDS.
•  Drive the vehicle under FREEZE FRAME DATA (Mode 2) condition.
•  Retrieve the DTC using the M-MDS.
•  Is the PENDING CODE for this DTC present?
Yes
Replace the SCR control unit, then go to the next step.
No
Go to the next step.
9
VERIFY AFTER REPAIR PROCEDURE
•  Perform the “AFTER REPAIR PROCEDURE”.
•  Are any DTCs present?
Yes
Go to the applicable DTC inspection.
No
DTC troubleshooting completed.