DD15 SPN 411/FMI 1 Troubleshooting

SPN 411/FMI 1

This diagnosis is typically EGR differential pressure failed (Low Box).‪

Check as follows:‪

1. Visually inspect the EGR system for leaks, obstructions, loose clamps or damage.
   1. If damage is found, repair as necessary, clear the fault code and retest.
   2. If no damage is found, go to the next step.
2. Turn the Ignition OFF.
3. Disconnect the EGR Delta P Sensor connector.
4. Inspect connector for damaged, corroded, bent or spread pins.
   1. If pin damage is found, repair as necessary.
   2. If no damage is found, go to the next step.
5. Remove the EGR Delta P Sensor.
6. Inspect the passages in the EGR venturi pipe for blockage or obstruction.
   1. If passages are blocked, clean as necessary and retest.
   2. If no blockage is found replace EGR Delta P Sensor. Refer to “39.2.1 Verify Repairs” .

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 7.0 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.‪

4. Start and bring engine up to operating temperature (over 140°F/60°C).
5. Verify operation is satisfactory and no warning lamps illuminate. If warning lamps illuminate, troubleshoot the codes.