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DD15 Noisy 1-Box

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This diagnostic is used to identify the cause of a noisy 1-BOX™ Aftertreatment.

Check as follows:

  1. Visually inspect the entire exhaust system for signs of leaks or damage. Is any damage found?
    1. Yes; repair as necessary.
    2. No;Go to step 2.
  2. Inspect that the aftertreatment inlet heat shields are not broken loose and rattling. Is there a loose or damaged heat shield?
    1. Yes; repair the heat shield. If the inlet heat shield has tabs, refer to 11 TS-6 .
    2. No; Go to step 3.
  3. Inspect the inboard and outboard Diesel Particulate Filter (DPF) covers and verify nothing is loose or rattling. Is there a loose DPF cover?
    1. Yes; repair the loose cover.
    2. No; Go to step 4.
  4. Turn off engine after inspection.
  5. Disconnect the aftertreatment inlet pipe and start the engine to verify the noise is coming from the aftertreatment. Did the noise go away once the aftertreatment inlet pipe was disconnected?
    1. Yes; reconnect the aftertreatment inlet pipe and Go to step 6.
    2. No; inspect other truck components to identify the noise.
  6. Connect DiagnosticLink® .
  7. Start the engine and run a Parked Regen. Monitor Diesel Oxidation Catalyst (DOC) inlet pressure and engine speed during the regen.

NOTICE:

If DOC inlet pressure is 19.9 kPa (2.9 psi) or higher at any time during the parked regen, immediately stop the regen because turbocharger damage may occur and Go to step 18.

  1. Review the last seven minutes of the parked regeneration log data. The illustration below identifies the last seven minutes of the parked regen.
  1. Is the Selective Catalyst Reduction (SCR) inlet temperature lower than SCR outlet temperature by more than 38°C (68.4°F)?
    Example : SCR Outlet temp 587°C (1090°F) minus SCR Inlet Temp 398°C (749°F) = 116°C (241°F). The difference between inlet and outlet temperature is 116°C (241°F), which is greater than 20.2°C (68.4°F).
    1. Yes; Go to step 10.
    2. No; Go to step 11. for log file review.
  1. Perform a low temperature Aftertreatment Device (ATD) check using DiagnosticLink to check for a drifted temperature sensor. Are the SCR inlet and SCR outlet temperatures within 25°C (45°F) during the last five minutes of this test?
    1. Yes; replace the DOC/SCR module. This indicates internal structural damage; see image below. The ATD checklist is NOT required since the ATD is the primary failed part.
    1. No; replace the drifted SCR temperature sensor and Go to step 11.
  1. Review the parked regen log file. Compare your DOC inlet pressure reading to the screen shots below (steps 12, 13, and 14) to identify a possible cause of the aftertreatment noise.
  2. Is the DOC Inlet Pressure starting out high above 10 kPa (1.45 psi) and decreases during a parked regen?
    1. Yes; Go to step 15.
    2. No; Go to step 13.
DOC inlet pressure (orange line) started at 16kPa (2.32 psi) and dropped to 5kPa (0.72 psi) during a full regen.
  1. Is the DOC inlet pressure starting above the pressure specified below and stays high?
EPA10 10 KPa (1.45 psi)
GHG14 6 KPa (.89 psi)
GHG14 DD15 AT Only 7 KPa (1.01 psi)
    1. Yes; Go to step 16.
    2. No; Go to step 14.
DOC inlet pressure (orange line) started at 6 kPa (0.87 psi) and stayed there throughout the regen. The slight spikes seen in the pressure reading are due to the fan turning on/off.
  1. When the DOC inlet pressure starts out low and stays low , below 3.1 kPa (.45 psi), the Aftertreatment System (ATS) is considered noisy. Replace the DOC/SCR module. This indicates internal structural damage; see image below. The ATD checklist is NOT required since the ATD is the primary failed part. Verify repair.
DOC inlet pressure (orange line) starts out low and stays low, below 10 KPa (1.45 psi) the ATS is considered noisy. The noise may be more present between 7 to 9 KPa (1.01 psi – 1.30 psi).
  1. This indicates that the DPFs were plugged and the parked regen has cleared them. Verify the noise is gone and complete the ATD check list to possibly identify why the unit was plugged.
  2. The DOC is considered plugged. Since the DOC inlet pressure stayed steady and there is still a noise, run the DOC Face Unplugging procedure in DiagnosticLink under Actions-Aftertreatment. After completing the service routine, verify the noise is gone. Go to step 17.
  3. Review DDEC reports to find out if excessive engine idle time is the cause of the plugged DOC.
  4. The DOCs are severely face plugged. After cleaning, verify the noise is gone and release the vehicle.

 

3609/ FMI 4 Diesel Oxidation Catalyst Inlet Pressure sensor circuit failed low

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    1. Check for multiple codes.
        1. If SPN 3609/FMI 4 and SPN 3610/FMI 4 are present, repair open between Aftertreatment Control Module (ACM) pin 117 and Diesel Oxidation Catalyst (DOC)/Diesel Particulate Filter (DPF) pressure sensors pin 3.

      1. If only SPN 3609/FMI 4 is presentGo to step 2.

    1. Turn the ignition OFF (key OFF, engine OFF).

    1. Disconnect the DOC inlet pressure sensor.

    1. Inspect the DOC inlet pressure sensor harness for bent, spread, or corroded pins.
        1. If the pins are bent, spread, or corroded, repair as necessary.

      1. If the connector shows no signs of damage,Go to step 5.

    1. Disconnect the ACM 120-pin connector.

    1. Measure the resistance between pin 2 of the DOC inlet pressure sensor and ground.
        1. If the resistance is less than 1k ohms, repair short to ground between pin 2 of the DOC inlet pressure sensor and pin 87 of the ACM 120-pin connector.

      1. If the resistance is greater than 1K ohmsGo to step 7.

  1. Measure the resistance between pin 2 of the DOC inlet pressure sensor and pin 87 of the ACM 120-pin connector.
      1. If the resistance is greater than 3 ohms repair wire between pin 2 of the DOC inlet pressure sensor and pin 87 of the ACM 120-pin connector.

    1. If the resistance is less than 3 ohms, replace the DOC inlet pressure sensor

157/ FMI 18 Fuel Rail Pressure Too High

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Description Fuel Rail Pressure Too High
Monitored Parameter Fuel Rail Pressure
Typical Enabling Conditions Closed Loop and Actual RP Greater than 200 Bar of Desired RP
Monitor Sequence None
Execution Frequency Continuous When Enabling Conditions Met
Typical Duration 8 Seconds
Dash Lamps MIL, CEL
Engine Reaction Derate 25%
Verification Steady Engine 1400 – 1500 rpm (two minutes)

The Motor Control Module (MCM) monitors the fuel rail pressure, and when fuel rail pressure deviation is greater than 200 bar higher than requested fuel rail pressure for eight seconds, the MCM sets the code. This fault can occur due to the conditions listed below:

  • Faulty fuel rail pressure sensor
  • Faulty Quantity Control Valve (QCV)
  • Faulty MCM
  • Faulty Wiring

    1. Turn the ignition ON (key ON, engine OFF).

    1. Using DiagnosticLink® , check for multiple codes. Are additional codes, excluding ACM codes, present along with SPN 157/FMI 18?
        1. Yes; troubleshoot the additional codes first.

      1. No; Go to step 3.

    1. Check actual fuel rail pressure (key ON, engine OFF). Is actual fuel rail pressure greater than 5 bar?
        1. Yes; Go to step 4.

      1. No; Go to step 5.

    1. Remove the fuel rail pressure sensor and reconnect the sensor to the harness.  Is the fuel rail pressure sensor reading greater than 5 bar with sensor removed from rail?
        1. Yes; replace the fuel rail pressure sensor. 

      1. No; install the removed fuel rail pressure sensor. Go to step 5.

    1. Perform the Fuel System Integrity Check (FSIC) test using DiagnosticLink® .

    1. Is the actual fuel rail pressure (ASL001) 200 bar higher than the desired rail pressure (AS098) at any point during the FSIC test?
        1. Yes; replace the quantity control valve.

      1. No; the deviation is less than 200 bar, Go to step 7.

  1. Inspect the fuel rail pressure sensor connector and MCM 120-pin connector for corrosion, bent, spread, or damaged pins. Is any damage found?
      1. Yes; replace the damaged component.

    1. No; replace the fuel rail pressure sensor. 

164/ FMI 21 FUEL RAIL PRESSURE SENSOR DRIFT LOW

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EPA07/10/GHG14 DDEC VI/10 Electronics and Troubleshooting Manual (DDC-SVC-MAN-0084) | 90 SPN 164 (MCM) (EPA10;GHG14) | 90.6 SPN 164/FMI 21 – EPA10 – GHG14

Description Fuel Rail Pressure Sensor – Drift Low
Monitored Parameter Fuel Rail Pressure Sensor
Typical Enabling Conditions Key On & Engine Off
Monitor Sequence None
Execution Frequency Once when enabling conditions met
Typical Duration 10 Seconds
Dash Lamps MIL, CEL
Engine Reaction Derate 25%
Verification Key On & Engine Off

d150221

Check as follows:

    1. Disconnect the fuel rail pressure sensor.

    1. Inspect the fuel rail pressure sensor connector and harness connector for signs of damage: bent, spread, broken, unseated (pushed out) or corroded pins, signs of water intrusion or damaged wiring near the connector.
        1. If signs of damage are present, repair as necessary.

      1. If no signs of damage are present, Go to step 3.

    1. Turn the ignition ON (key ON, engine OFF).

    1. Measure the voltage between pins 1 and 3 of the fuel rail pressure sensor harness connector.
      1. If the voltage is between 4.5 and 5.5 volts, Go to step 6.

      1. If the voltage is not between 4.5 and 5.5 volts, Go to step 5.

    1. Measure the voltage between pin 3 of the fuel rail pressure sensor harness connector and battery ground.
        1. If the voltage is between 4.5 and 5.5 volts, repair the wire between pin 1 of the fuel rail pressure sensor harness connector and pin 102 of the MCM 120-pin connector.

      1. If the voltage is not between 4.5 and 5.5 volts, repair the wire between pin 3 of the fuel rail pressure sensor and pin 58 of the MCM 120-pin connector.

    1. Turn the ignition OFF.

    1. Disconnect the MCM 120-pin connector.

    1. Inspect the MCM 120-pin connector and harness connector for signs of damage; bent, spread, broken, unseated (pushed out) or corroded pins, signs of water intrusion or damaged wiring near the connector.
        1. If signs of damage are present, repair as necessary.

      1. If no signs of damage are present, Go to step 9.

    1. Measure the resistance between pin 2 of the fuel rail pressure sensor harness connector and pin 78 of the MCM 120-pin connector.
        1. If the resistance is less than 5 ohms, Go to step 10.

      1. If the resistance is greater than 5 ohms, repair the wire between pin 2 of the fuel rail pressure sensor harness connector and pin 78 of the MCM 120-pin connector.

    1. Measure the resistance between pin 3 of the fuel rail pressure sensor harness connector and pin 58 of the MCM 120-pin connector.
        1. If the resistance is less than 5 ohms, Go to step 11.

      1. If the resistance is greater than 5 ohms, repair the wire between pin 3 of the fuel rail pressure sensor harness connector and pin 58 of the MCM 120-pin connector.

    1. Measure the resistance between pins 1 and 2 of the fuel rail pressure sensor harness connector.
        1. If the resistance is greater than 10K ohms, Go to step 12.

      1. If the resistance is less than 10K ohms, repair the short in the wires between pins 1 and 2 of the fuel rail pressure sensor harness connector.

    1. Reconnect the MCM 120-pin harness connector.

    1. Turn the ignition ON (key ON, engine OFF).

  1. Measure the voltage between pins 1 and 3 of the fuel rail pressure sensor harness connector.
      1. If the voltage is between 4.5 and 5.5 volts, replace fuel rail pressure sensor. 

    1. If the voltage is not between 4.5 and 5.5 volts, repeat the above procedure. If the results are the same, replace the MCM module. 

4334/ FMI 3 DIESEL EXHAUST FLUID PRESSURE SENSOR CIRCUIT FAILED HIGH

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Description This code sets when the Aftertreatment Control Module (ACM) detects a short to voltage or open on the Diesel Exhaust Fluid (DEF) Pressure Sensor Circuit
Monitored Parameter Diesel Exhaust Fluid (DEF) Pressure Sensor
Typical Enabling Conditions Always Enabled
Monitor Sequence None
Execution Frequency Always Enabled
Typical Duration 2 Seconds
Dash Lamps MIL, CEL
Engine Reaction Derate 25%
Verification Engine Idle (1 minute)

d150275

    1. Connect DiagnosticLink® . Go to step 2.

    1. Turn the ignition ON (Key ON, Engine OFF). Go to step 3.

    1. Check for multiple codes. Are codes SPN 4335/FMI 3 or SPN 3510/FMI 3 also present?
        1. Yes; Go to step 4.

      1. No; Go to step 9.

    1. Turn the ignition OFF. Go to step 5.

    1. Disconnect the DEF air pressure sensor electrical connector. Go to step 6.

    1. Turn the ignition ON (Key ON, Engine OFF). Go to step 7.

    1. Measure the voltage between pin 3 of the DEF pressure sensor connector, harness side and ground. Is the voltage greater than 5 volts?
        1. Yes; repair the short to power on pin 84 of the 120-pin ACM connector. Verify repair.

      1. No; Go to step 8.

    1. Measure the voltage between pin 3 of the DEF pressure sensor connector, harness side and ground. Is the voltage between 4.5 and 5 volts?
        1. Yes; repair the open circuit between pin 2 of the DEF pressure sensor and pin 99 of the 120-pin ACM connector.

      1. No; repair the open circuit between pin 3 of the DEF pressure sensor and pin 84 of the 120-pin ACM connector. Verify repair.

    1. Turn the ignition OFF. Go to step 10.

    1. Disconnect the DEF pressure sensor. Measure the voltage between pin 3 of the DEF pressure sensor connector, harness side and ground. Is the voltage between 4.5 and 5 volts?
        1. Yes; Go to step 11.

      1. No; repair the open between pin 3 of the DEF pressure sensor connector and the circuit splice. Verify repair.

  1. Measure the voltage between pin 2 of the DEF pressure sensor connector, harness side and pin 3 of the DEF pressure sensor connector, harness side. Is the voltage between 4.5 and 5.0 volts?
      1. Yes; replace the DEF pressure sensor. Verify repair.

    1. No; repair the open between pin 2 of the DEF pressure sensor connector and the circuit splice. Verify repair.

1659/ FMI 1 THERMOSTAT MONITOR ERROR DETECTED

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Description Thermostat Error Detected
Monitored Parameter Coolant Inlet temperature sensor
Typical Enabling Conditions Always Enabled
Monitor Sequence None
Execution Frequency Once Per Drive Cycle
Typical Duration 30
Dash Lamps MIL
Engine Reaction
Verification Allow Engine to Cool Down Such That Coolant Inlet Temperature is Less Than 50°C (122°F), Drive Vehicle for 30 Minutes, Preferably with a Trailer (Loaded or Unloaded), Do Not Idle Engine Except When Necessary

 

    1. Are any cooling system issues present?
        1. Yes; repair cooling system issues first.

      1. No; Go to step 2.

    1. Check for other fault codes. Is fault code SPN 110/FMI Any or SPN 4193/FMI Any also present?
        1. Yes; diagnose other fault code first.

      1. No; Go to step 3.

To avoid injury before starting and running the engine, ensure the vehicle is parked on a level surface, parking brake is set, and the wheels are blocked.

    1. Start engine and bring to operating temperature to 85°C (185°F).

    1. Does engine reach operating temperature 85°C (185°F).
        1. Yes; Go to step 5.

      1. No; replace the engine cooling system thermostat. 

    1. Shut engine OFF.

    1. Disconnect inlet and outlet coolant temperature sensors.

    1. Inspect inlet and outlet coolant temperature sensors, harness connectors for bent, spread or corroded pins.
        1. If pin damage is found, repair as necessary.

      1. If no pin damage is found, Go to step 8.

  1. Check coolant sensor resistance; refer to chart for specifications, replace sensor which is out of range.

    Coolant Sensor Resistance Chart
    Temp °C Temp °F Resistance (Ω) Nominal Resistance Low (Ω) Resistance High (Ω) Nominal Voltage (V) Voltage Low (V) Voltage High (V)
    0 32 5872.8 5496.4 6249.2 2.56 2.51 2.61
    10 50 3769 3640.3 3897.7 2.37 2.33 2.41
    20 68 2480.7 2260.0 2701.4 2.14 2.05 2.22
    30 86 1693.2 1613.4 1773.0 1.89 1.83 1.95
    35 95 1401.1 1338.4 1463.8 1.75 1.69 1.81
    40 104 1166.8 1117.5 1216.1 1.62 1.56 1.67
    50 122 829.5 798.2 860.8 1.36 1.30 1.41
    60 140 593.8 574.5 613.1 1.12 1.07 1.17
    70 158 435.4 423.1 447.7 0.91 0.86 0.95

3936/ FMI 18 DIESEL PARTICULATE FILTER (DPF) PRESSURE OUT OF RANGE LOW

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Description This Fault Code Sets when the Diesel Oxidation Catalyst (DOC) Inlet Pressure and Diesel Particulate Filter (DPF) Outlet Pressure delta is Below Normal Operating Range for More than 10 Seconds
Monitored Parameter DOC Inlet Pressure Sensor and DPF Outlet Pressure Sensor
Typical Enabling Conditions Always On
Monitor Sequence None
Execution Frequency Continuous When Enabling Conditions Met
Typical Duration Two Seconds
Dash Lamps MIL, CEL, SEL
Engine Reaction Derate 25%
Verification Run Engine Between 1200 to 1800 rpm With a Load Less Than 10%

 

    1. Visually inspect entire exhaust system for signs of leaks or damage. Are there any leaking or damaged exhaust components?
        1. Yes; repair as necessary.

      1. No; Go to step 2.

    1. Connect DiagnosticLink® .

    1. Using the Selective Catalytic Reduction (SCR) voltage service routine, monitor the Diesel Oxidation Catalyst (DOC) inlet pressure (pin 87) and DPF outlet pressure (pin 72) voltages with the key ON, engine OFF.

    1. Are the DOC inlet and DPF outlet pressure sensors voltages between .44 to .56 volts?
        1. Yes; Go to step 6.

      1. No; Go to step 5.

    1. Inspect electrical connections between suspect sensor connector and Aftertreatment Control Module (ACM) for bent, spread, or corroded pins. Is there any damage found?
        1. Yes; repair as necessary.

      1. No; replace the sensor with the voltage reading outside of the 0.44-0.56 volts.
    1. Inspect the DOC and DPF pressure sensor tubes and elbows for leaks, kinks, or blockages. Were any leaks, kinks or blockages found?
        1. Yes; repair as necessary.

      1. No; Go to step 7.

 

    1. Start the engine and run a Parked Regen. During the last 10% of the parked regen period, is the Selective Catalyst Reduction (SCR) inlet temperature more than 38°C (68.4°F) lower than SCR outlet temperature?
        1. Yes; Go to step 8.

      1. No; Go to step 9.

    1. Perform a low temperature Aftertreatment Device (ATD) check using DiagnosticLink to check for a drifted temperature sensor.  Are the SCR inlet and SCR outlet temperatures within 25°C (45°F) during the last five minutes of this test?
        1. Yes; replace the DOC/SCR module. This indicates an internal failure of the DOC/SCR module.

      1. No; replace the drifted SCR temperature sensor. Go to step 9.

  1. During the parked regen, does either the DOC inlet pressure or DPF outlet pressure sensor drop to 0.0 psi?
      1. Yes; replace the failed sensor.

    1. No; clear fault and release unit. The code likely occurred after extended idle and soot buildup has cleared.

2659/ FMI 1 EXHAUST GAS RECIRCULATION FLOW TARGET ERROR (LOW FLOW)

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    1. This troubleshooting applies to EPA07 DD13 engines ONLY; for EPA07 DD15, you must use the Advanced Diagnostic troubleshooting in DiagnosticLink® .

    1. Check for multiple codes.
        1. If any of the following codes are present, troubleshoot and repair them first:
          • SPN 411/FMI (any)
          • SPN 1636/FMI (any)
          • SPN 2791/FMI (any)
          • SPN 3563/FMI (any)
          • SPN 2630/FMI (any)

      1. If there are no other codes present, Go to step 3.

    1. Ensure Motor Control Module (MCM) software is version 13.2 ZGS003 or higher.

    1. Visually inspect the entire Exhaust Gas Recirculation (EGR) and exhaust system (turbine housing, exhaust manifold, etc.) for evidence of external leakage (e.g. soot, coolant deposits at joints).
        1. If external leakage is found, repair as necessary.

      1. If no external leakage is found, Go to step 5.

    1. Remove the delta P sensor from the mounting pad; leave the electrical harness connected.

    1. Inspect the delta P sensor for moisture inside the ports. Shake moisture out if necessary; do not replace the sensor.

    1. Inspect the delta P venturi ports for clogging and blockage. A layer of soot on the delta P sensor is OK.
        1. If no blockage is found, Go to step 8.

      1. If blockage is found, clean venturi ports. Do not replace delta P sensor.

    1. Turn the ignition ON (key ON, engine OFF).

    1. Using DiagnosticLink® , monitor delta P voltage (pin 109).

    1. Is the delta P voltage between 0.55 and 0.83 volts?
        1. Yes; Go to step 13.

      1. No; Go to step 11.

    1. Disconnect the delta P sensor harness connector.

    1. Inspect the delta P sensor harness connector for loose, bent, spread or corroded pins.
        1. If pin damage is found, repair as necessary.

      1. If no connector damage is found, replace delta P sensor. After sensor replacement, perform delta P re-calibration service routine and release the vehicle. Refer to section “Removal of the Delta P Sensor” .

    1. With key ON and engine OFF, compare inlet manifold pressure value with the barometric pressure value. Are the values within 1.5 psi (10.3 kPa) of each other?
        1. Yes; Go to step 14.

      1. No; inspect the inlet manifold pressure sensor and wiring for damage.

    1. Inspect the inlet manifold temperature sensor and the Charge Air Cooler (CAC) outlet temperature sensor connectors for corrosion.
        1. If no evidence of corrosion is found, Go to step 15.

      1. If evidence of corrosion is found, replace the affected temperature sensor and pigtail. Inspect the MCM 120-pin connector for corrosion and repair as necessary.

    1. Remove EGR cooler hot pipe, EGR crossover pipe and delivery pipe and inspect for excessive build up or blockage.
        1. If excessive build up or blockage is found, clean piping and replace EGR cooler. Refer to section “Removal of the DD13 Exhaust Gas Recirculation Cooler Water Manifold Assembly” .

      1. If there is no excessive build up or blockage, Go to step 16.

  1. Inspect the EGR valve for physical damage (broken butterfly, etc.).
      1. If the EGR valve is damaged, replace the center section of the exhaust manifold. Refer to section “Removal of the Exhaust Manifold” .

    1. If no damage is found, obtain a log file of the fault going active

NORMAL FUEL SYSTEM PRESSURES – THREE FILTER SYSTEM

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Normal and abnormal fuel system pressures are listed in the following tables. The pressures can vary slightly due to different chassis fuel line configurations, fuel temperatures, fuel filter condition, and fuel viscosity.

Normal Fuel System Pressures
Port Engine 600 RPM Engine 1800 RPM
LPP Inlet (in Hg) -4 to -8 -11 to -14
LPP Outlet (PSI) 72 to 80 100 to 126
HPP Inlet (PSI) 69 to 77 92 to 112
HPP Outlet (PSI) 1 to 2.5 4 to 7
Priming Port (PSI) 72 to 80 100 to 120
Fuel Compensation pressure w/ doser regulator 75 to 85 80 to 95

If the LPPI is greater than the specified range, check for inlet restrictions.

If the high pressure pump Inlet pressure is lower than the acceptable pressure, check the pressure difference across the low pressure pump outlet pressure sensor and fuel compensation pressure sensor. If engine does not have a low pressure pump outlet pressure sensor, install J-48876 and use priming port pressure.

157/ FUEL RAIL PRESSURE TOO LOW

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EPA07/10/GHG14 DDEC VI/10 Electronics and Troubleshooting Manual (DDC-SVC-MAN-0084) | 81 SPN 157 (MCM) (EPA07;EPA10;GHG14) | 81.1 SPN 157/FMI 16 – EPA07 – EPA10 – GHG14

Description Fuel Rail Pressure Too Low
Monitored Parameter Injector Cylinder #1 Needle Control Valve
Typical Enabling Conditions Fuel Rail Pressure desired – Fuel Rail Pressure Actual > 200 bar
Monitor Sequence None
Execution Frequency Continuous When Enabling Conditions Met
Typical Duration Eight Seconds
Dash Lamps MIL, CEL
Engine Reaction Derate 25%
Verification Engine Idle (One Minute)

The Motor Control Module (MCM) monitors the rail pressure and when rail pressure deviation is greater than 200 bar for eight seconds, the MCM sets the code. This fault can occur due to the conditions listed below:

  • External fuel leakage between the high pressure pump and fuel injectors
  • Pressure limiting valve leakage (internal)
  • Fuel filter integrity (loose caps, plugged filters)
  • Fuel supply issues (fuel level, fuel aeration, leaking fuel lines, fuel restrictions)
  • Intermittent loss of engine speed signal
  • High pressure pump internal failure
  • Fuel injector (amplifier or needle) leakage
  • Fuel Contamination
  • Rail pressure sensor
  • Motor Control Module (MCM)

 

Service Tools Used in the Procedure
Tool Number Description
J-48876 Test Gauge, Primer Port, HDE
J-48704 Caps, HP Fuel Rail, HDE
DiagnosticLink 8.x

NOTE: It is important to obtain information from the customer on when the check engine lamp occurs and if there were any performance concerns or exhaust smoke.

 

    1. Did SPN 157/FMI 16 appear after the fuel system was repaired or fuel filter maintenance was performed?
        1. Yes; the code may be set due to air in the fuel system. Clear codes and road test to verify complaint. If code does not set, release the vehicle. If code sets, Go to step 2.

       

      1. No; Go to step 2.

 

    1. Turn the ignition ON (key ON, engine OFF).
NOTE: On EPA10 engines with MCM software 7.6 and later, fuel tank level at the time the fault triggered can be viewed in extended data #5, “Enhanced Environmental data” Fuel Tank Level.

 

    1. Check and record fuel level in all fuel tanks. Is fuel level blow ¼ tank (25%)?
        1. Yes; add fuel and road test vehicle. If code does not become active during road test, release the truck. If the code becomes active during the road test with over ¼ tank (or 25%) of fuel, Go to step 4.

       

      1. No; view fuel tank level in extended data (EPA10) or question the driver about the fuel level when the code was set. If the level was under ¼ tank (or 25%), fuel sloshing in the tank could be the cause of aerated fuel that could cause this code. If the fuel level was over ¼ tank (or 25%) when the code was set, Go to step 4.

 

    1. Check for fuel contamination, including Diesel Exhaust Fluid (DEF), water, gasoline, kerosene, coolant, etc. Is contamination found?
        1. Yes; refer to section “Contaminated Fluids.”

       

      1. No;Go to step 5.

 

    1. Visually inspect for external fuel leaks on the engine and on the chassis.
        1. If a leak is found, repair leak. 

       

      1. If no leaks are found, Go to step 6.

 

    1. Using DiagnosticLink 8.x, check for multiple codes.
        1. If any of the additional fault codes are active, perform the associated diagnostics first:
          • SPN 94 / FMI 15 Fuel Filter plugged
          • SPN 94 / FMI 16 Fuel Filter plugged
          • SPN 97 / FMI 15 Water in the fuel
          • SPN 157 / FMI 1 Rail Pressure too High.
          • SPN 164 / FMI (All) Rail pressure sensor faults
          • SPN 174 / FMI 0 Fuel Temperature too High
          • SPN 679 / FMI 7 PLV stuck open
          • SPN 723 / FMI (all) Cam Sensor Codes
          • SPN 636 / FMI (all) crank sensor codes
          • SPN 1077 / FMI 5, 6 or 14

       

      1. If only SPN 1077/7, 157/16 or 1077/31 is present, Go to step 7.
NOTE: Do not reset this counter unless the PLV is being replaced.

 

    1. Using DiagnosticLink 8.x, check the value of Pressure Limiting Valve (PLV) openings. With key ON, engine OFF select the Actions tab in the top tool bar. Select Fuel System, then Pressure Limiting Valve (PLV) Change or view (E2P_RPG_CTR_PLV_OPEN) under “Extended Data Record Number 5th” list. View and record the PLV open counts. Is the counter greater than 50?
        1. Yes; replace the PLV. Verify repairs. 

       

      1. No;Go to step 8.
NOTE: Engines not equipped with a Low Pressure Pump Outlet (LPPO) sensor should utilize J-48706 Fuel Diagnostic Gauge Set to monitor LPPO.

 

    1. Perform Automatic Fuel system integrity check (FSIC) routine using DiagnosticLink 8.x. With key ON, Engine OFF (KOEO) start the Automatic FSIC. The software/tool will ask to start the engine when required. Once the engine is running, the software will have the engine enter and exit several engine operating conditions. Once the engine shuts down, leave the key on for five minutes. Disconnect DDDL and open the log file. The next part of the troubleshooting will require reviewing the FSIC log file. Go to step 9.

 

    1. Monitor rail pressure bleed-off time. Is bleed-off time below 35 seconds?
        1. Yes; using DiagnosticLink, perform the HP Leak Test.

       

      1. No; Go to step 10.

 

    1. Is the rail pressure bleed-off time is greater than 2 minutes 30 seconds?
        1. Yes; perform the Idle Speed Balance Test to identify faulty injector.

       

      1. No; Go to step 11.

 

    1. Does Kw/Nw show/stay “ON / Enabled / True” while the engine is running during the Automatic FSIC routine?
        1. Yes; Go to step 12.

       

      1. No; refer to troubleshooting for SPN 723/FMI 10.

 

    1. Was the fuel temperature rise greater than 10 degrees?
        1. Yes; Go to step 14.

       

      1. No; Go to step 13.

 

    1. At 600 rpm, is ASL003 Fuel Compensation Pressure within range per the fuel pressure chart? 
        1. Yes; Go to step 15.

       

      1. No; Go to step 14.

 

    1. Monitor AS124 LPPO sensor (if equipped) or use manual gauge J-48706. Is the pressure in range at 600 and 1800 rpm? 
        1. Yes; Go to step 15.

       

      1. No; Repair cause of incorrect fuel pressure. 

 

    1. Monitor AS124 LPPO (if equipped) and ASL003 Fuel Compensation Pressure at all engine speeds, are pressures stable with no oscillations?
        1. Yes; Go to step 16.

       

      1. No; pressures are unstable WITH oscillations of more than 1.5 psi at a steady rpm, 

 

    1. Check the Idle Speed Balance (ISB) Values. Are there any cylinders above 70% or below -70%?
        1. Yes; Follow repair procedures in “Idle speed balance (ISB) test” and verify repairs. 

       

      1. No; Go to step 17.

 

    1. Is ASL001 Rail Pressure erratic or does it have a saw tooth pattern?
      d500085
      d500086

       

        1. Yes; Go to step 18.
      NOTE: See examples of erratic pressure showing (1) ASL001 Rail pressure and (2) AS098 Desired rail pressure.

       

      1. No; Go to step 19.

 

    1. Perform the aerated fuel test.  Was fuel aerated?
        1. Yes; repair cause of aerated fuel. 

       

      1. No; replace the Quantity Control Valve. 

 

    1. Perform Pressure Limiting valve flow test. Did the PLV flow test pass?
        1. Yes; Go to step 20.

       

      1. No; replace the PLV. 

 

    1. Inspect the Low pressure fuel system for leaks . Are leaks present?
        1. Yes; Repair as necessary. 
      NOTICE:

      Prime fuel system prior to going to next step.

       

      1. No; Go to step 21.

 

    1. Cap the rail at all six injector feed connections using J-48704 injector rail caps and crank the engine for 10 seconds. Does the ASL001 rail pressure reach AS098 desired rail pressure?
        1. Yes; Go to step 22.

       

      1. No; Replace high pressure pump. .

 

    1. With the injectors still capped after cranking engine for 10 seconds, does the rail pressure bleed down under 100 bar in less than five minutes?
        1. Yes; Replace the high pressure fuel pump.

       

      1. No; Go to step 23.

 

    1. Using DiagnosticLink 8.x, navigate to Service Routines and Fuel System Integrity Check test and select Manual FSIC. Test drive the truck to see if the code sets. Did the code become active?
        1. Yes; Go to step 24.

       

      1. No; replace fuel filters and release vehicle to customer.

 

    1. Remove the MCM 120-Pin connector. Inspect for damage including fuel, water corrosion or bent terminals. Is any damage found?
        1. Yes; repair as needed.

       

      1. No; Go to step 25.

 

    1. Install a test MCM using the extension harness and test drive the truck. Does the Code come active?
        1. Yes; Go to step 26.

       

      1. No; replace MCM and verify repair.

 

  1. Inspect chassis fuel system for restrictions or debris. Refer to OEM procedures. Is there a chassis fuel system issue?
      1. Yes; identify source of issue and repair as necessary.

     

    1. No; replace fuel filters and release to customer.