id0102f3166400
| DTC P20DF:00 |
Urea pump pressure sensor circuit low |
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DETECTION CONDITION
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• The SCR control unit monitors input voltage from urea pump pressure sensor while the engine switch is on. If the input voltage is
below 0.2 V for 2 sec., the SCR control unit determines that the urea pump pressure sensor circuit voltage is low.
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.
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POSSIBLE CAUSE
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• Urea pump pressure sensor short cord connector or terminal malfunction
• Short to ground in wiring harness between urea pump pressure sensor terminal 1 and SCR control unit terminal 26
• Short to ground in wiring harness between boost sensor terminal 2 and SCR control unit terminal 60
• SCR control unit connector or terminal malfunction
• Urea pump pressure sensor signal circuit and ground circuit are shorted to each other
• Open circuit in the wiring harness between urea pump pressure sensor terminal 1 and SCR control unit terminal 26
• Urea pump pressure sensor connector or terminal malfunction
• Urea pump pressure sensor malfunction
• SCR control unit malfunction
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Diagnostic procedure
| STEP |
INSPECTION |
ACTION |
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|---|---|---|---|
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1
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VERIFY FREEZE FRAME DATA AND DIAGNOSTIC MONITORING TEST RESULTS HAS BEEN RECORDED
• Have FREEZE FRAME DATA (mode2) or snapshot data been recorded?
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Yes
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Go to the next step.
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No
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Record the FREEZE FRAME DATA (mode2) and snapshot data on the repair order, then go to the next step.
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2
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VERIFY RELATED SERVICE INFORMATION AVAILABILITY
• Verify related Service Information availability.
• Is any related Service Information available?
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Yes
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Perform the repair or diagnosis according to the available Service Information.
• If the vehicle is not repaired, go to the next step.
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No
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Go to the next step.
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3
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VERIFY CURRENT SIGNAL STATUS: IS CONCERN INTERMITTENT OR CONSTANT?
• Clear the DTC from the PCM memory using the M-MDS.
• Start the engine.
• Is the PENDING CODE for this DTC present?
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Yes
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Go to the next step.
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No
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Intermittent concern exists.
Perform the “INTERMITTENT CONCERN TROUBLESHOOTING”.
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4
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INSPECT UREA PUMP PRESSURE SENSOR SHORT CORD CONNECTOR FOR POOR CONNECTION
• Switch the ignition off.
• Disconnect the urea pump pressure sensor short cord connector.
• Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
• Is there any malfunction?
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Yes
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Repair or replace the terminal, then go to Step 14.
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No
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Go to the next step.
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5
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INSPECT UREA PUMP PRESSURE SENSOR CIRCUIT FOR SHORT TO GROUND
• Urea pump pressure sensor short cord connector is disconnected.
• Switch the ignition off.
• Inspect for continuity between the following terminals and body ground:
• Is there continuity?
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Yes
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If the short to ground circuit could be detected:
• Repair or replace for a possible short to ground.
If the short to ground circuit could not be detected:
• Replace the SCR control unit (short to ground in SCR control unit internal circuit). (See
SCR CONTROL UNIT REMOVAL/INSTALLATION [MZR-CD 2.2].)
Then go to Step 14.
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No
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Go to the next step.
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6
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INSPECT SCR CONTROL UNIT CONNECTOR FOR POOR CONNECTION
• Switch the ignition off.
• Disconnect the SCR control unit connector.
• Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
• Is there any malfunction?
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Yes
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Repair or replace the terminal, then go to Step 14.
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No
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Go to the next step.
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7
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INSPECT UREA PUMP PRESSURE SENSOR SIGNAL AND GROUND CIRCUITS FOR SHORT TO EACH OTHER
• Urea pump pressure sensor short cord and SCR control unit connectors are disconnected.
• Inspect for continuity between urea pump pressure sensor short cord terminals D and E (SCR control unit-side).
• Is there continuity?
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Yes
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Repair or replace the malfunctioning wiring harness, then go to Step 14.
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No
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Go to the next step.
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8
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INSPECT UREA PUMP PRESSURE SENSOR CIRCUIT FOR OPEN CIRCUIT
• Urea pump pressure sensor and SCR control unit connectors are disconnected.
• Switch the ignition off.
• Inspect for continuity between the urea pump pressure sensor short cord (SCR control unit-side) terminal C and SCR control unit terminal (wiring harness-side) 26.
• Is there continuity?
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Yes
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Go to the next step.
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No
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Repair or replace the wiring harness for possible open circuit, then go to Step 14.
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9
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INSPECT UREA PUMP PRESSURE SENSOR CONNECTOR FOR POOR CONNECTION
• Switch the ignition off.
• Disconnect the urea pump pressure sensor connector.
• Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
• Is there any malfunction?
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Yes
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Repair or replace the terminal, then go to Step 14.
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No
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Go to the next step.
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10
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INSPECT UREA PUMP PRESSURE SENSOR CIRCUIT FOR SHORT TO GROUND
• Urea pump pressure sensor and short cord connectors are disconnected.
• Switch the ignition off.
• Inspect for continuity between the following terminals and body ground:
• Is there continuity?
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Yes
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Repair or replace the wiring harness for possible short to ground circuit, then go to Step 14.
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No
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Go to the next step.
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11
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INSPECT UREA PUMP PRESSURE SENSOR SIGNAL AND GROUND CIRCUITS FOR SHORT TO EACH OTHER
• Urea pump pressure sensor and short cord connectors are disconnected.
• Inspect for continuity between urea pump pressure sensor short cord terminals D and E (urea pump pressure sensor-side).
• Is there continuity?
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Yes
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Repair or replace the malfunctioning wiring harness, then go to Step 14.
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No
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Go to the next step.
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12
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INSPECT UREA PUMP PRESSURE SENSOR CIRCUIT FOR OPEN CIRCUIT
• Urea pump pressure sensor and SCR control unit connectors are disconnected.
• Switch the ignition off.
• Inspect for continuity between the urea pump pressure sensor (urea pump pressure sensor-side) terminal C and urea pump pressure sensor terminal (wiring harness-side) 1.
• Is there continuity?
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Yes
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Go to the next step.
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No
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Repair or replace the wiring harness for possible open circuit, then go to Step 14.
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13
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INSPECT UREA PUMP PRESSURE SENSOR
• Inspect the urea pump pressure sensor. (See
SCR SYSTEM INSPECTION [MZR-CD 2.2].)
• Is there any malfunction?
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Yes
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Replace the urea pump, then go to the next step.
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No
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Go to the next step.
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14
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VERIFY TROUBLESHOOTING OF DTC P20DF:00 COMPLETED
• Make sure to reconnect all disconnected connectors.
• Clear the DTC from the SCR control unit memory using the M-MDS.
• Switch the ignition ON for 2 sec.
• Retrieve the DTC using the M-MDS.
• Is the PENDING CODE for this DTC present?
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Yes
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Replace the SCR control unit, then go to the next step.
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No
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Go to the next step.
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15
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VERIFY AFTER REPAIR PROCEDURE
• Perform the “AFTER REPAIR PROCEDURE”. (See
AFTER REPAIR PROCEDURE [MZR-CD 2.2].)
• Are any DTCs present?
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Yes
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Go to the applicable DTC inspection.
(See
DTC TABLE [MZR-CD 2.2].)
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No
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DTC troubleshooting completed.
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