LEMON Manuals: Even more car manuals for everyone
Home >> Ford >> 1996 >> Aerostar Van Window >> Repair and Diagnosis >> External Pages >> Different car >> Section 199 (Engine Controls - Tests W/Codes - 7.3L Diesel - EEC-IV) >> Pinpoint Tests >> Pinpoint Test H: Exhaust BACKPRESSURE Sensor >> Diagnostic Aids

Diagnostic Aids

WARNING: This page does not describe the selected car, but rather 14 other vehicles, including the 1996 Ford RV Cutaway, 1996 Ford Pickup, 1996 Ford F-Super Duty, 1996 Ford Econoline, and 1996 Ford Cutaway. However, it is still accessible from the selected car via links, so may be relevant.

  1. 1) KOEO DTC 0470

    This DTC indicates PCM detected EBP sensor malfunction during KOEO SELF-TEST . Possible causes for this DTC are:
    • Faulty EBP sensor.
    • Open or shorted circuit.
    • Faulty PCM.

    Ensure scan tool is connected to Data Link Connector (DLC). See VEHICLE PREPARATION & EQUIPMENT HOOKUP  under QUICK TEST. Using scan tool, access EBP PID from PID/DATA MONITOR & RECORD menu. If EBP reading is less than 18.5 psi, clear DTCs and repeat KOEO SELF-TEST . If DTC is still present, replace PCM. If EBP reading is 18.5 psi or more, go to next step.

  2. 2) Check Signal Ground Circuit

    Turn ignition off. Disconnect EBP sensor connector. Sensor is located on top of engine. Inspect for damaged pins, corrosion and loose wires. Repair as necessary. Measure resistance between ground and Gray/Red wire at EBP sensor wiring harness connector. If resistance is less than 5 ohms, replace EBP sensor. Clear DTCs, and repeat QUICK TEST . If resistance is 5 ohms or more, locate and repair open circuit in Gray/Red wire. Clear DTCs, and repeat QUICK TEST .

  3. 3) Continuous Memory DTC 0470

    This DTC indicates PCM detected a EBP sensor malfunction during normal driving conditions. Possible causes for this DTC are:
    • Faulty EBP sensor.
    • Faulty connection.
    • Faulty PCM.

    Ensure scan tool is connected to Data Link Connector (DLC). See VEHICLE PREPARATION & EQUIPMENT HOOKUP  under QUICK TEST. Using scan tool, access EBP PID from PID/DATA MONITOR & RECORD menu. While observing EBP PID, wiggle and bend small sections of wiring harness starting at EBP sensor connector and working toward PCM. If EBP reading fluctuates, isolate fault and repair as necessary. Clear DTCs, and repeat QUICK TEST . If reading does not fluctuate, go to next step.

  4. 4) Check Connector

    Disconnect EBP sensor connector. Sensor is located on top of engine. Disconnect PCM 104-pin connector. Inspect connectors for damaged pins, corrosion and loose wires. Repair as necessary. Clear DTCs, and repeat QUICK TEST . If both connectors are okay, no problem is indicted at this time, Clear DTCs, and repeat QUICK TEST.

  5. 5) Continuous Memory DTC 0471

    This DTC indicates PCM detected an EBP sensor malfunction during normal driving conditions, and with EBP sensor enabled. Possible causes for this DTC are:
    • Faulty EBP sensor.
    • Plugged or restricted sensor supply tube.
    • Damaged Exhaust Pressure Regulator (EPR) linkage or butterfly damage.
    • Faulty PCM.

    Perform KOER SELF-TEST . If any DTCs are present, repair fault(s) before continuing with this test. Using scan tool, access EBP PID from PID/DATA MONITOR & RECORD menu. Road test vehicle performing hard accelerations while monitoring EBP PID. If EBP reading increases to more than 25 psi with EBP sensor on, no problem is indicated at this time. Clear DTCs, and repeat QUICK TEST . If EBP reading does not increase to more than 25 psi, go to next step.

  6. 6) Check For Exhaust Leaks

    Inspect turbo pipe, crossover pipes, and exhaust manifolds for leaks. Repair as necessary. Clear DTCs, and repeat QUICK TEST . If no exhaust leaks are present, go to next step.

  7. 7) Check Sensor Supply Tube

    Inspect EBP sensor supply tube from exhaust manifold to sensor bracket. Ensure tube is not restricted or plugged. Replace tube as necessary. Clear DTCs, and repeat QUICK TEST . If tube is okay, go to next step.

  8. 8) Check EBP Sensor

    Disconnect EBP sensor connector. Install ICP/EBP Adapter Cable (D94T-50-A) between EBP sensor and sensor wiring harness connector. Start engine. Measure voltage between signal circuit and signal ground at ICP/EBP adapter cable. Briefly accelerate engine to Wide Open Throttle (WOT) several times. If voltage reading during acceleration is more than 1.35 volts, clear DTCs and repeat QUICK TEST . If DTC is still present, replace PCM. If voltage reading during acceleration is not more than 1.35 volts, replace EBP sensor. Clear DTCs, and repeat QUICK TEST .

  9. 9) DTC 0472: EBP Circuit Low Input

    This DTC indicates EBP sensor circuit low input was detected during KOEO SELF-TEST  or during continuous diagnostic monitoring. Possible causes for this DTC are:
    • Biased sensor/PCM.
    • Open or shorted EBP sensor circuit.
    • EBP sensor circuit shorted.
    • Faulty PCM.

    Turn ignition off. Disconnect EBP sensor connector. Sensor is located on top of engine. Turn ignition on. Measure voltage between ground and Purple/Light Blue wire at EBP sensor wiring harness connector. If voltage is 4.5-5.5 volts, go to next step. If voltage is not 4.5-5.5 volts, locate and repair open circuit in Brown/White wire (VREF circuit). Clear DTCs, and repeat QUICK TEST .

  10. 10) Check SIG RTN Circuit

    Measure resistance between ground and Gray/Red wire at EBP sensor wiring harness connector. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, locate and repair open circuit in Gray/Red wire. Clear DTCs, and repeat QUICK TEST .

  11. 11) Check EBP Signal Circuit

    Turn ignition off. Disconnect PCM 104-pin connector, and inspect for damaged pins, corrosion and loose wires. Repair as necessary. Install Breakout Box (014-00950), leaving PCM disconnected. Measure resistance between Purple/Light Blue wire at EBP sensor wiring harness connector and test pin No. 30 at breakout box. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, locate and repair open circuit in Purple/Light Blue wire. Clear DTCs, and repeat QUICK TEST .

  12. 12) Check VREF Circuit

    Measure resistance between Brown/White wire at EBP sensor wiring harness connector and test pin No. 90 at breakout box. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, locate and repair open circuit in Brown/White wire. Clear DTCs, and repeat QUICK TEST .

  13. 13) Check For Grounded EBP Signal Circuit

    Measure resistance between test pin No. 30 and test pins No. 29, 51, 76, 77, 91 and 103. If all readings are more than 10 k/ohms, go to next step. If any reading is less than 10 k/ohms, locate and repair short to ground in EBP signal circuit (Purple/Light Blue wire). Clear DTCs, and repeat QUICK TEST .

  14. 14) Check For Internal PCM Short

    Connect PCM connector to breakout box. Measure resistance between test pin No. 30 and test pins No. 29, 51, 76, 77, 91 and 103. If all readings are more than 10 k/ohms, replace EBP sensor. Clear DTCs, and repeat QUICK TEST . If any reading is 10 k/ohms or less, replace PCM. Clear DTCs, and repeat QUICK TEST .

  15. 15) DTC 0473

    This DTC indicates EBP sensor circuit high input was detected during KOEO SELF-TEST  or during continuous diagnostic monitoring. Possible causes for this DTC are:
    • Biased sensor/PCM.
    • EBP sensor shorted to VREF circuit.
    • Faulty PCM.

    Turn ignition on. Disconnect EBP sensor connector. Sensor located on top of engine. Perform KOEO SELF-TEST . If DTC 0473 present, replace EBP sensor. Clear DTCs, repeat QUICK TEST . If DTC 0473 is not present, go to next step.

  16. 16) Check For Short To Power

    Disconnect PCM 104-pin connector, and inspect for damaged pins, corrosion and loose wires. Repair as necessary. Install Breakout Box (014-00950), leaving PCM disconnected. Measure resistance between test pin No. 30 and test pins No. 55, 71, 90 and 97 at breakout box. If all readings are more than 10 k/ohms, replace PCM. Clear DTCs, and repeat QUICK TEST . If any reading is 10 k/ohms or less, locate and repair short to power in Purple/Light Blue wire. Clear DTCs, and repeat QUICK TEST .

  17. 17) DTC 0478

    This DTC indicates excessive backpressure existed during normal driving. Possible causes for this DTC are:
    • Stuck butterfly.
    • Plugged EBP sensor tube.
    • Restricted exhaust.
    • Misadjusted Exhaust Pressure Regulator (EPR) linkage.
    • Faulty PCM.

    Visually inspect exhaust backpressure control valve. If control valve is open, go to next step. See Fig 1. If control valve is not open, repair damaged linkage or butterfly as necessary. Clear DTCs, and repeat QUICK TEST .

    Fig 1: Open Exhaust Backpressure Control Valve Position
    G95I35277

  18. 18) Check For Exhaust Restriction

    Ensure scan tool is connected to Data Link Connector (DLC). Using scan tool, access EBP PID from PID/DATA MONITOR & RECORD menu. Start engine. Briefly accelerate engine speed to Wide Open Throttle (WOT) while monitoring EBP PID. If EBP PID reading is less than 28 psi, go to next step. If EBP PID reading is 28 psi or more, repair restricted exhaust system. Clear DTCs, and repeat QUICK TEST .

  19. 19) Check EBP System

    Ensure engine is cold. Engine Oil Temperature (EOT) less than 70°F (21°C) and IAT less than 45°F (7°C). Road test vehicle while monitoring EBP PID reading on tester. With EBP sensor on, if EBP reading stays at less than 50 psi, replace PCM. Clear DTCs, and repeat QUICK TEST . With EBP sensor on, if EBP reading does not stay at less than 50 psi, check and adjust Exhaust Pressure Regulator (EPR) as necessary.
scientia non olet · About LEMON Manuals