hi my 1991 lexus ls400 has a problem, when i turn on the parking or headlights, the R(reverse) light comes on, on the dash, as if i am in reverse and the car does not shift correctly at all. It sticks in one gear and then hesitates to shift around 3k rpms, sometimes it misses the gear, then as soon as i turn the lights off, the car runs and shifts through the gears absolutely fine, what could this be caused by?