You need to remove the flasher relay. It should be similar to this:
Open up the flasher and look for this resistor:
You will need to change this resistor to make your signal blink faster, or slower. The resistance is around 90K If you want to make your signal blink twice as fast as stock, then you would replace the resistor with a 45K.
The lower the resistance, the faster it will blink.
But his problem sounds like a short.