SPN 411/FMI 1 This diagnosis is typically EGR differential pressure failed (Low Box).‪ Check as follows:‪ Visually inspect the EGR system for leaks, obstructions, loose…

SPN 411/FMI 0 This diagnosis is typically EGR differential pressure failed high (Low Box).‪ Check as follows:‪ Disconnect the EGR Delta P Sensor. Inspect the…

SPN 411/FMI 4 This diagnosis is typically EGR Delta P Sensor short to ground.‪ Check as follows:‪ Disconnect the EGR Delta P Sensor. Disconnect the…

SPN 411/FMI 3 This diagnosis is typically EGR Delta P Sensor circuit failed high.‪ Check as follows:‪ Disconnect the EGR Delta P Sensor. Measure the…

SPN 523/FMI 13 This fault is typically the transmission current gear signal is missing.‪ Check as follows:‪ Check for multiple codes: If CPC SPN 168/FMI…

SPN 527/FMI 9 This fault is typically the J1939 CCVS message from Source #1, #2, or #3 is missing.‪ Check as follows:‪ Check for multiple…

SPN 523/FMI 9 This fault is typically the J1939 ETC2 message is missing.‪ Check as follows:‪ Check for multiple codes: If CPC SPN 168/FMI 0/14/18…

SPN 558/FMI 1 This fault is a typically incorrect wiring of the Idle Validation Switch (IVS).‪ Check as follows:‪ Connect the diagnostic tool Turn ignition…

SPN 558/FMI 4 This diagnostic condition is typically either a short to ground or an open wire.‪ Check as follows:‪ Disconnect the Idle Validation Switch.…