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 elements)
- Injector (amplifier or needle) leakage
- Pressure limiting valve leakage (internal)
Check as follows:
- Check for multiple codes
- If additional fault codes are present along with 1077/15, service the additional fault codes first
- If only 1077/15 is present go to the next step.
- Turn the ignition OFF.
- Inspect the following fuel system components for external leakage: high pressure pump, lines to fuel rail, fuel rail, pressure limiting valve (PLV), and fuel lines from rail to injector.
- If leakage was found, repair and refer to “81.4.1 Verify Repairs” .
- If no leakage was found, go to next step.
- Perform rail pressure bleed off test. Refer to “16.9.1 RPBO Test Using DDDL” , “RPBO Test using DDDL.”
- If the RPBO test failed; go to next step.
- If the RPBO test passed, no problem found.
- Perform pressure limiting valve (PLV) leakage test. Refer to “16.10 Pressure Limiting Valve Leakage” , “Pressure Limiting Valve Leakage.”
- If the pressure limiting valve (PLV) test passed; go to next step.
- If the pressure limiting valve (PLV) test failed; replace pressure limiting valve and refer to “81.4.1 Verify Repairs” .
- Perform amplifier/needle return measurements. Refer to “16.6 High Amplifier/Needle Return Flow (Version 4 Fuel System)” , “High Amplifier/Needle Return Flow”.
- If the amplifier/needle return flow test passed; no problem found.
- If the amplifier/needle return flow test failed; fix as necessary and refer to “81.4.1 Verify Repairs” .
Verify repairs as follows:
- Turn ignition OFF.
- Reconnect any electrical connections that were disconnected to perform the diagnosis.
- Clear codes with DDDL 7.0 or latest version.
ENGINE EXHAUST To avoid injury from inhaling engine exhaust, always operate the engine in a well-ventilated area. Engine exhaust is toxic.
- Start and bring engine up to operating temperature (over 140°F/60°C).
- Verify operation is satisfactory and no warning lamps illuminate. If warning lamps illuminate, troubleshoot the codes.