[my427cobra]

Hi all y'all. Now it's my turn for turn signal wiring woes. I have researched all the old threads and they all have a common theme: grounding problems . Well that dosent seem to be my problem so here it is :

1) Set-up : 2 lamps in front with 1157 (2 filiment) bulbs (wired for park lite and turn signals), 4 lamps in back all with 1157 bulbs(top lamp wired for park lite and brake lite, bottom lamp wired for park lite and turn signal).

2) All lites good and brite with park and headlites ON and with park lites only ON. No grounding problems here.
Brake lites work great on brite filament.
NO TURN SIGNALS WORK.

3) With park lites and headlites OFF, ALL SIGNAL LITES WORK GREAT.
Turn the park or park and headlites ON , NO TURN SIGNALS WORK.

Anybody have any suggestions?
For some reason , turning the park and headlights on seems to cancel out the turn signal circuit.

Hope someone can help.
Greg