Sounds like you may have an incorrect bulb in one of the left turn-signal housings.
If your "parking light" socket needs a two filament bulb (the kind with two contacts on the bottom) and a single filament bulb was put into that socket the result is the pair of socket-connectors (each meant for one of the contacts on the bottom of a dual-filament bulb) will be shorted together by the single-filament contact.
This will effectively connect your turn-signal circuit for the left side to your parking light/panel light circuit all the time.
The result is that if the parking lights are on, the single filament will be powered and back-feed the turn-signal circuit on the left side, but if the parking lights are off, then the left turn signal will power the single filament and back-feed the parking light circuit (which also feeds the radio and clock lights in your dashboard).
Hope this helps
Problem most likely is in the Turn Signal switch. I had same problem , replaced Turn Signal switch assembly and that fixed it.
Of course because you turned your blinker on yes it is.
Problem may be in the steering column (turn signal stalk)
Check the Hazard warning switch
when you flip your blinker on, a relay in the circuit is activated which turns the light on and off. also, the front blinker and rear blinker usually alternate in turning off and on, so when the back is on, the front will be off, and reverse.. that's why when a bulb is out, the clicking sound in the vehicle goes faster than when both are in working order.
change the bulb out for the brake light and that fixes the problem.
Turn signal bulbs and hazard bulbs are the same bulb. When the turn signal is turned on, the indicator light on the dash flashes in tune with the turn signal. When the hazard lights are turned on, an extra fuse which is live, powers the hazard flashers, even if the car is turned off.
i don't know if it is a Ford thing, but my dodge did somewhat the same thing... my blinker would flash very fast on the dash and it turned out that my bulbs were out in the rear (maybe that is the problem and your brake lights are connected). When the bulbs burn out the circuit is shorted.
That sounds like a grounding problem, probably near the right side lights. It might be a rusty or disconnected ground wire.
Watson turned up the gas (lights) less than halfway on his way out to summon Mr Culverton Smith, and this was presumably a signal for Inspector Morton of Scotland Yard to make himself known to Dr Watson. Then, later, Culverton Smith turned up the gas (lights) to full at the request of Holmes, and this was a signal (unknown to Culverton Smith) for Inspector Morton to enter the apartment.
a bulb is out
A mis-wiring or short circuit somewhere between the controls, fusebox and lights.