PPAP Level 3 for J1939 Alternators: What a Ripple-to-Bus Coupling Test Should Contain
A 24 V alternator passes the battery-terminal ripple gate at 180 mV peak-to-peak. The PSW is signed. Eighteen months later, the OEM’s warranty database shows a cluster of J1939 communication DTCs on units built in the same production window. The ripple was never the variable that failed; the coupling path was. What we see repeatedly […]