996 Reversing Lights Issue

[Rics911]

2004 Porsche 911 Carrera Coupe. Tiptronic transmission. Reversing lights are inoperable. Fuse B5 and bulbs good. 12v present at B5 with shifter in “R”. With both bulbs removed from tail light assemblies and shifter in “R”, 12v is present at both sockets. Placing one bulb in either socket causes voltage drop to 0. Measuring 1.9k ohm between socket (+) and gnd. Has anyone experienced this issue or something similar? Any suggestions will be greatly appreciated. Thanks.