DTC P1406 [YF (2.0L Zetec)]

id0102d0825200

DTC P1406

D.P.F. EGR sensor downstream hose off or plugged

DETECTION CONDITION

• The PCM monitors differential pressure across the EGR orifice when the EGR valve from open to close. If the PCM detects that the signal from D.P.F. EGR sensor continues to indicate EGR flow even after the EGR valve is commanded closed, the PCM determines D.P.F. EGR sensor upstream hose off or plugged.

POSSIBLE CAUSE

• Downstream hose is disconnected
• Downstream hose is plugged (ice)
• Plugged or damaged EGR tube

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.
No
Record the FREEZE FRAME DATA on the repair order, then go to the next step.
2
VERIFY REPAIR INFORMATION AVAILABILITY
• Verify related service 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.
No
Go to the next step.
3
INDETIFY TRIGGER DTC FOR FREEZE FRAME DATA
• Is DTC P1406 on FREEZE FRAME DATA?
Yes
Go to the next step.
No
Go to FREEZE FRAME DATA DTC inspection.
4
INSPECT DOWNSTREAM PRESSURE HOSE CONNECTIONS
Note
• If the fault is currently present, DTC P1408 will be output in KOER self test.
• Inspect downstream hose at D.P.F. EGR sensor and orifice tube assembly for disconnect or poor connection.
• Is hose off or poor connection?
Yes
Repair for hose connection properly, then go to the Step 8.
No
Go to the next step.
5
INSPECT DOWNSTREAM PRESSURE HOSE FOR PLUGGING
Note
• It is essential that the D.P.F. EGR pressure hose used is the connect repair part and not a substitute.
• Visually inspect downstream pressure hose routing. Hose must not be pinched or have dips in it where water could settle or plugging, water or leaks.
• Remove downstream pressure hose and carefully inspect for plugging, water or leaks.
• Is there a fault detected in the hose?
Yes
Repair or replace malfunctioning pressure hose, then go to Step 8.
No
Go to the next step.
6
CHECK ORIFICE TUBE ASSEMBLY AND D.P.F. EGR SENSOR
• Inspect the upstream connection on the D.P.F. EGR sensor for plugging or damage at the sensor.
• Inspect the exhaust manifold side pressure pickup tube at the orifice assembly for plugging or damage.
• Is the D.P.F. EGR sensor or orifice tube assembly plugged or damaged?
Yes
Repair or replace D.P.F. EGR sensor or orifice tube assembly.
Then go to Step 8.
No
Go to the next step.
7
CHECK D.P.F. EGR SENSOR OUTPUT BY APPLYING VACUUM WITH HAND PUMP
• Connect the WDS or equivalent to DLC-2.
• Disconnect pressure hoses at D.P.F. EGR sensor.
• Connect a hand vacuum pump to the downstream connection at sensor (intake manifold side of sensor or smaller diameter pickup tube.)
• Turn the ignition switch to ON.
• Access DPFEGR PID and note PID value.
• Apply 27-30 kPa {8-9 inHg} vacuum to the D.P.F. EGR sensor and hold for a few seconds.
• Quickly release vacuum.
- The DPFEGR PID voltage must be between 0.2 and 1.3 V with the ignition switch ON and no vacuum applied.
- The DPFEGR PID voltage must increase to greater than 4.0 V with the vacuum applied.
- The DPFEGR PID must drop to less than 1.5 V in less than 3 s when vacuum is released.
• Does DPFEGR PID voltage indicate a fault in the D.P.F. EGR sensor?
Yes
Replace D.P.F. EGR sensor, then go to the next step.
No
Unable to duplication or identify fault at this time.
Go to the next step.
8
VERIFY TROUBLESHOOTING OF DTC P1406 COMPLETED
• Make sure to reconnect all disconnected connectors.
• Clear the DTC from the PCM memory using the WDS or equivalent.
• Drive the vehicles from a stop, accelerate to 72 km/h {45 MPH} at 1/2 to 3/4 throttle. Repeat 3 times.
• Is the PENDING CODE same DTC present?
Yes
Replace PCM, then go to the next step.
No
Go to the next step.
9
VERIFY AFTER REPAIR PROCEDURE
• Perform "After Repair Procedure".
• Is there any DTC present?
Yes
Go to the applicable DTC inspection.
No
Troubleshooting completed.