-> What am I doing wrong????
->
-> Any help is appreciated.
You're not doing anything wrong!  That's the nature of the beast.  If
one source is supplying power to any given bulb filament, you can't
BLINK it from another source.  Turn signal switches are fairly complex
and there's no immediately SIMPLE way of overcoming this.
The most obvious way is to provide a separate single filament bulb
snuggled into the lamp-housing and connected only to the turn signal
circuit.  Thus you have one circuit for tail lights controlled by the
headlight switch. Nother circuit for brake lights controlled by the
brakelight switch, and yet another discrete circuit on each side
controled by each position of the turn signal switch.  (That's actually
the way most modern cars do it.  Saves unbelievable complexity in the
various controlling switches.
BTW, you may hear other ideas, some of which may actually work, but take
my word for it, I've been doing things of this nature for nearly fifty
years, and the above is the PRACTICAL way of solving the problem.
 ^..^
--- FidoPCB v1.5 beta-'j'
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