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HOMESERVICE MANUALSMAZDA2008TRIBUTE I SPORT, FWD, STANDARDREPAIR AND DIAGNOSISENGINE PERFORMANCEFUEL DELIVERYSYMPTOM TROUBLESHOOTING [ENGINE/FUEL - EXCEPT HYBRID]DIFFERENTIAL PRESSURE FEEDBACK (DPFEGR) SENSOR MALFUNCTION
2008 Mazda Tribute i Sport, FWD, Standard

Differential Pressure Feedback (DPFEGR) Sensor Malfunction

2008 Mazda Tribute i Sport, FWD, StandardSECTION Differential Pressure Feedback (DPFEGR) Sensor Malfunction
PROBLEM SYMPTOMS CHART - DIFFERENTIAL PRESSURE FEEDBACK (DPFEGR) SENSOR MALFUNCTION

DTC P0405, P0406 DPFEGR SENSOR MALFUNCTION
DETECTION CONDITION
  • P0405 indicates the average voltage of the DPFEGR SIG circuit input is below the minimum (0.2 V).
  • P0406 indicates the average voltage of the DPFEGR SIG circuit input is above the maximum (4.5 V).
POSSIBLE CAUSES
  • DPFEGR SIG shorted to GND (P0405)
  • DPFEGR SIG open (P0406)
  • DPFEGR SIG shorted to PWR (P0406)
  • VREF shorted to PWR (P0406)
  • VREF shorted to GND (P0405)
  • SIG RTN open (P0406)
  • Damaged DPFEGR sensor (P0405, P0406)
  • Damaged PCM (P0405, P0406)
HINT DPFEGR Sensor Description 
  • Measures the actual pressure drop across the metering orifice and relays a proportional voltage signal (0 to 5 V) to the PCM.
G05463740
INSPECTION CHART - DIFFERENTIAL PRESSURE FEEDBACK (DPFEGR) SENSOR MALFUNCTION

STEP INSPECTION ACTION
1 PCM QUICK TEST
  • Was PCM Quick Test carried out? 
 Yes For DTC P0405: GO to the next step.
For DTC P0406: GO to step 6.
No CARRY OUT the PCM Quick Test. See PCM QUICK TEST  .
2 DTC P0405: VERIFY DIFFERENTIAL PRESSURE FEEDBACK EGR (DPFEGR) VOLTAGE
NOTE:
  • Depending on the application, verify a prior repair has not resulted in the differential pressure feedback EGR sensor being installed backwards of the vacuum hoses being installed on the opposite ports.
  • Key ON, engine OFF (KOEO).
  • Using IDS or equivalent tester, select Diagnostic Data Link.
  • Access the PCM and monitor the DPFEGR PID.
  • Is the DPFEGR PID voltage less than 0.05 V? 
 Yes The DPFE sensor voltage is less than the acceptable minimum.
GO to the next step.
No Fault is intermittent.
GO to step 13.
3 INDUCE OPPOSITE DPFEGR SENSOR VOLTAGE
  • Disconnect DPFEGR sensor connector.
  • Key ON, engine OFF (KOEO).
  • Using IDS or equivalent tester, select Diagnostic Data Link.
  • Access the PCM and monitor the DPFEGR PID.
  • Is DPFEGR PID value between 4.0 and 5.5 V? 
 Yes Replace DPFE sensor.
See DIFFERENTIAL PRESSURE FEEDBACK EXHAUST GAS RECIRCULATION (EGR) SYSTEM SENSOR - 3.0L (4V) REMOVAL/INSTALLATION .
GO to step 14.
No GO to the next step.
4 MEASURE VREF VOLTAGE AT DPFEGR SENSOR VEHICLE HARNESS CONNECTOR
  • Key ON, engine OFF (KOEO).
  • Measure voltage between VREF and SIG RTN at the DPFEGR sensor harness connector.
  • Key OFF.
  • Was VREF voltage between 4.0 and 5.5 V? 
 Yes GO to the next step.
No VREF voltage is out-of-range.
See TEST 1: VEHICLE REFERENCE VOLTAGE (VREF)  .
5 CHECK DPFE CIRCUIT FOR SHORTS TO VREF AND SIG RTN
  • Disconnect IDS or equivalent tester from DLC.
  • Disconnect PCM.
  • Measure resistance between PCM pin E44 (DPFEGR SIG) and PCM pin E41 (SIG RTN)
  • Measure resistance between PCM pin E44 (DPFEGR SIG) and PCM pin E40 (VREF).
  • Is each resistance greater than 10K ohms? 
 Yes REPLACE PCM.
See POWERTRAIN CONTROL MODULE (PCM) - 2.3L REMOVAL/INSTALLATION .
GO to step 14.
No REPAIR short circuit.
GO to step 14.
6 DTC P0406: VERIFY DPFEGR PID VOLTAGE
  • Key ON, engine OFF (KOEO).
  • Access DPFEGR PID with IDS or equivalent tester.
  • Key OFF.
  • Was DPFEGR PID voltage greater than 4.0 V? 
 Yes The DPFEGR sensor voltage is greater than the acceptable maximum.
GO to the next step.
No The fault is intermittent.
GO to step 13.
7 VERIFY THAT VREF IS IN RANGE
  • Key ON, engine OFF (KOEO).
  • Measure voltage between the sensor VREF and SIG RTN at DPFEGR sensor harness connector.
  • Key OFF.
  • Was VREF voltage between 4.0 and 5.5 V? 
 Yes GO to the next step.
No VREF is out-of-range.
See TEST 1: VEHICLE REFERENCE VOLTAGE (VREF)  .
8 CHECK DPFEGR SIG CIRCUIT FOR OPEN IN HARNESS
  • Disconnect PCM.
  • Measure resistance of DPFEGR SIG circuit between PCM pin E44 and DPFEGR sensor harness connector.
  • Is resistance less than 5.0 ohms? 
 Yes GO to the next step.
No REPAIR open circuit.
GO to step 14.
9 CHECK SIG RTN FOR OPEN IN HARNESS
  • Measure resistance of DPFEGR SIG RTN circuit between PCM pin E41 and DPFEGR sensor harness connector.
  • Is resistance less than 5.0 ohms? 
 Yes GO to the next step.
No REPAIR open circuit.
GO to step 14.
10 CHECK DPFEGR SIG FOR SHORT TO VREF IN HARNESS
  • Disconnect PCM.
  • Measure the resistance between PCM pin E44 (DPFEGR SIG) and PCM pin E40 (VREF).
  • Is resistance greater than 10K ohms? 
 Yes GO to the next step.
No REPAIR short circuit.
GO to step 14.
11 CHECK DPFEGR SIG FOR SHORT TO PWR
  • Disconnect DPFEGR sensor harness connector.
  • Key ON, engine OFF (KOEO).
  • Measure voltage between DPFEGR SIG circuit at the DPFEGR sensor harness connector and battery ground.
  • Key OFF.
  • Was voltage less than 0.2 V? 
 Yes GO to the next step.
No REPAIR short circuit.
GO to step 14.
12 CHECK THE DPFEGR PID
  • Key OFF.
  • Connect a 5 amp fused jumper wire between the sensor DPFEGR SIG and SIG RTN circuits at the DPFEGR sensor harness connection.
NOTE:
  • If a IDS or equivalent tester communication concern exists, remove the jumper immediately and GO to step 13.
  • Key ON, engine OFF (KOEO).
  • Using IDS or equivalent tester, select Diagnostic Data Link.
  • Access the PCM and monitor the DPFEGR PID.
  • Is the DPFEGR PID greater than 4.5V with the jumper wire removed and is the DPFEGR PID less than 0.1V with the jumper wire installed? 
 Yes REPLACE DPFEGR sensor.
See DIFFERENTIAL PRESSURE FEEDBACK EXHAUST GAS RECIRCULATION (EGR) SYSTEM SENSOR - 3.0L (4V) REMOVAL/INSTALLATION .
GO to step 14.
No GO to the next step.
13 WIGGLE TEST DPFEGR SENSOR AND HARNESS
  • Key ON, engine OFF (KOEO).
  • Using IDS or equivalent tester, select Diagnostic Data Link.
  • Access the PCM and monitor the DPFEGR PID.
  • Observe DPFEGR PID for an indication of fault while carrying out the following:
    • Lightly tap on DPFEGR sensor; wiggle the DPFEGR sensor connector and vehicle harness between sensor and PCM. A fault is indicated by a sudden change in DPFEGR PID voltage.
  • Is a fault indicated? 
 Yes ISOLATE fault and REPAIR as necessary.
GO to the next step.
No Unable to duplicate or identify fault at this time.
See TEST 3: INTERMITTENT  with DPFEGR PID data and list of possible causes.
14 VERIFY TROUBLESHOOTING OF DTCs COMPLETED
  • Disconnect all the PCM connectors.
  • Check for:
    • Corrosion
    • damaged pins
    • pushed-out pins
  • Connect all connectors and make sure they seat correctly.
  • Clear DTCs from PCM memory using IDS or equivalent tester generic OBD II tester.
  • Carry out the PCM Quick Test. See PCM QUICK TEST  .
  • Is the same DTC present? 
 Yes REPLACE PCM.
See POWERTRAIN CONTROL MODULE (PCM) - 2.3L REMOVAL/INSTALLATION .
REPEAT the PCM Quick Test. See PCM QUICK TEST  .
No If any other DTC is present, GO to applicable DTG inspection.
If no DTC is present, troubleshooting complete.


PROBLEM SYMPTOMS CHART - DIFFERENTIAL PRESSURE FEEDBACK (DPFEGR) SENSOR MALFUNCTION

DTC P1405, P1406 DPFEGR SENSOR MALFUNCTION
DETECTION CONDITION
  • P1405 indicates the exhaust manifold side (upstream) DPFEGR sensor pressure hose is off or plugged.
  • P1406 indicates the intake manifold side (downstream) DPFEGR sensor pressure hose is off or plugged.
POSSIBLE CAUSES
  • Upstream or downstream pressure hose disconnected or incorrectly connected
  • Upstream or downstream pressure hose plugged (by ice)
  • Plugged or damaged pressure pickup tubes
  • Damaged DPFEGR sensor
HINT DPFEGR Sensor Description
  • Measures the actual pressure drop across the metering orifice and relays a proportional voltage signal (0 to 5 V) to the PCM.
G05463742
INSPECTION CHART - DIFFERENTIAL PRESSURE FEEDBACK (DPFEGR) SENSOR MALFUNCTION

STEP INSPECTION ACTION
1 PCM QUICK TEST
  • Was PCM Quick Test carried out? 
 Yes GO to the next step.
No CARRY OUT the PCM Quick Test. See PCM QUICK TEST  .
2 INSPECT PRESSURE HOSE CONNECTIONS
G05463769
  • Inspect upstream or downstream hose at DPFEGR sensor and orifice tube assembly for disconnect or poor connection.
  • Is vacuum hose off or poorly connected? 
 Yes RECONNECT hose(s) or REPAIR as necessary.
GO to step 6.
No GO to the next step.
3 INSPECT PRESSURE HOSE FOR PLUGGING
NOTE:
  • It is essential that the DPFEGR pressure hose is the correct service part and not a substitute.
  • Visually inspect upstream or downstream hose routing. Hose should not be pinched or have dips in it where water could settle and freeze.
  • Remove upstream or downstream hose and carefully inspect for plugging, water or leaks.
  • Is a concern present? 
 Yes REPAIR or REPLACE hose(s) as necessary.
GO to step 6.
No GO to the next step.
4 CHECK ORIFICE TUBE ASSEMBLY AND DPFEGR SENSOR
  • Inspect connections at the DPFEGR sensor for plugging or damage at sensor.
  • Inspect the exhaust and intake manifold side pressure tube and orifice tube assembly for plugging, loose connection or damage.
  • Is DPFEGR sensor or orifice tube assembly plugged, loose or damaged? 
 Yes REPAIR or REPLACE DPFEGR sensor or orifice tube assembly as necessary.
See DIFFERENTIAL PRESSURE FEEDBACK EXHAUST GAS RECIRCULATION (EGR) SYSTEM SENSOR - 3.0L (4V) REMOVAL/INSTALLATION .
GO to step 6.
No GO to the next step.
5 CHECK DPFEGR SENSOR OUTPUT BY APPLYING VACUUM WITH HAND PUMP
  • Disconnect pressure hoses at DPFEGR sensor.
  • Connect a hand vacuum pump to downstream connection at sensor (intake manifold side of sensor or the smaller diameter pickup tube).
  • Key ON, engine OFF (KOEO).
  • Using IDS or equivalent tester, select Diagnostic Data Link.
  • Access the PCM and monitor the DPFEGR PID.
  • Apply 27-30 kPa (8-9 in-Hg) vacuum to the DPFEGR sensor and hold for a 10 seconds.
  • Quickly release vacuum.
    • The DPFEGR PID voltage must be between 0.25 and 1.3 volt with the key on and no vacuum applied.
    • The DPFEGR PID voltage must increase to greater than 4.0 volts with vacuum applied.
    • The DPFEGR PID voltage should drop to less than 1.5 volts in less than 3 secnds when vacuum is released.
  • Does DPFEGR PID voltage indicate a concern in the DPFEGR sensor? 
 Yes REPLACE the DPFEGR sensor.
See DIFFERENTIAL PRESSURE FEEDBACK EXHAUST GAS RECIRCULATION (EGR) SYSTEM SENSOR - 3.0L (4V) REMOVAL/INSTALLATION .
After installing the new DPFEGR sensor, TURN the key to the ON position for approximately 5 seconds before starting. This allows the PCM to calibrate the new differential pressure feedback EGR sensor. Failure to do this may result in an incorrect DTC P0402.
GO to the next step.
No Fault not found.
See TEST 3: INTERMITTENT  .
6 DRIVE CYCLE
  • Make sure to reconnect all disconnected connectors.
  • Clear DTCs from PCM memory using IDS or equivalent tester.
  • Carry out EVAP System Monitor Drive Cycle.
  • See ON BOARD DIAGNOSTIC (OBD) DRIVE CYCLE  .
  • Retrieve pending code.
  • Is same DTC present? 
 Yes REPLACE the PCM.
See POWERTRIN CONTROL MODULE (PCM) - 2.3L REMOVAL/INSTAILLATION .
GO to the next step.
No GO to the next step.
7 VERIFY TROUBLESHOOTING OF DTCs COMPLETED
  • Disconnect all the PCM connectors.
  • Check for:
    • Corrosion
    • damaged pins
    • pushed-out pins
  • Connect all connectors and make sure they seat correctly.
  • Clear DTCs from PCM memory using IDS or equivalent tester generic OBD II tester.
  • Carry on the PCM Quick Test. See PCM QUICK TEST  .
  • Is the same DTC present? 
 Yes REPLACE the PCM.
See POWERTRAIN CONTROL MODULE (PCM) - 2.3L REMOVAL/INSTALLATION .
REPEAT the PCM Quick Test. See PCM QUICK TEST  .
No If any other DTC is present, GO to applicable DTC inspection.
If no DTC is present, troubleshooting complete.
RENDER: 1.0x

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