DD 15 – Section 17.4 SPN 1077/FMI 15

Section 17.4
SPN 1077/FMI 15

The fault condition is typically related to an internal or external leakage of the high pressure fuel system. The MCM monitors the rail pressure and when a leakage rate is greater than 100 l/h, the MCM sets the code. There is no fault reaction (limp home mode) associated to this code. This fault can occur due to the conditions listed below:‪

• External fuel leakage between the high pressure pump and injectors
• High pressure pump (pumping element failures)
• Injector (amplifier or needle) leakage
• Pressure limiting valve leakage (internal)

Check as follows:‪

1. Check for multiple codes.
   1. If additional fault codes are present along with 1077/15, service the additional fault codes first.
   2. If only 1077/15 is present go to step 2.
2. Turn the ignition OFF.
3. Inspect the following fuel system components for external leakage: high pressure pump, lines to fuel rail, fuel rail, PLV, and fuel lines from rail to injector.
   1. If leakage is found, repair and refer to "17.4.1 Verify Repairs" .
   2. If no leakage is found, go to next step.
4. Perform RPBO Test. Refer to "5.7.1 RPBO Test Using DDDL" , “RPBO Test using DDDL.”
   1. If the RPBO Test fails, go to next step.
   2. If the RPBO Test passes, no problem is present.
5. Perform PLV Leakage Test. Refer to "5.8 Pressure Limiting Valve Leakage" , “Pressure Limiting Valve Leakage.”
   1. If the PLV Leakage Test passes, go to next step.
   2. If the PLV Leakage Test fails, replace PLV and refer to "17.4.1 Verify Repairs" .
6. Perform Amplifier/Needle Return Flow Test and measurements. Refer to , “High Amplifier/Needle Return Flow.”
   1. If the Amplifier/Needle Return Flow Test passes, no problem is present.
   2. If the Amplifier/Needle Return Flow Test fails, fix as necessary and refer to "17.4.1 Verify Repairs" .

Section 17.4.1
Verify Repairs

Verify repairs as follows:‪

1. Turn ignition OFF.
2. Reconnect any electrical connections that were disconnected to perform the diagnosis.
3. Clear codes with DDDL 7.X.

   ENGINE EXHAUST ‪
   To avoid injury from inhaling engine exhaust, always operate the engine in a well-ventilated area. Engine exhaust is toxic.‪

4. Start and bring engine up to operating temperature (over 60°C/140°F).
5. Verify operation is satisfactory and no warning lamps illuminate. If warning lamps illuminate, troubleshoot the codes. If assistance is required, call the Detroit Diesel Customer Support Center at 313–592–5800.