Your turn signal is critical to letting other drivers know your intention, and if the other driver has the right of way, the driver is likely to move on. Your car's turn signal is a method used to signal to other drivers that you intend to turn or change lanes.
If you notice that the dashboard lights suddenly flicker at a faster rate, there may be a problem with the bulb. This is a fail-safe way to find out if your steering light bulb is working.
But in general, it doesn't let you know which (for example, left front or left back) causes the faster flicker. Still, it's a good way to at least let the driver know that the light bulb is no longer working.
Usually, the rear turn light bulb is in the taillight shade; this is just a matter of changing the bulb. The front part uses the same installation method, but it may be more difficult to access the front shell. In either case, light bulbs are cheap and readily available.