The problem was the X48/F connectors in the right passenger footwell, underneath the carpet housed in a black plastic cover, (10 inches forward of the right rear seat cushion red release button) particularly the red/red yellow positive power supply wires. Although the connector initially appears fine, once all the old hot glue shielding is removed, reveals totally corroded through, green separated wires! Since I was in there already, there are a total of 4 connectors on this 300ce, in the same area, so I just repaired all of them. All the connectors showed some deterioration with green corrosion but not like red wires.


There are several items including the passenger seat belt extender that splice into this portion of the wire harness for power, so if you experience start experiencing intermittent operation of certain items check/clean grounds and wire harness connector splices.