Ok guys, on my '88 S/C my passenger side turn signal marker and passenger side front running light will not come on with the headlights turned on. Both lights flash when I turn on passenger side blinker swith. They do not come on at all with just the headliughts on. I put a new bulb in the turn signal marker and this did not help. Should I try to replace front running light bulb, thinking filament might be burnt out.