Did you do something relate to electrical or unplug the battery? SRS light on is indication of passenger airbag is disable which under accident, it won't deploy! So if you did not do anything to the car at all and suddently the SRS light on, bring to the dealer to check out. IF under warranty, it will be fix for free. Better safe than sorry.
However, if the SRS light on due to the result of disconnected the battery or short circuit due to install electrical equipments, then there's an easy fix:
Here are the instructions for resetting the SRS light. (instructions copied from DareIL)
1. there is a Yellow 2 Pin connector with 2 greens wires in it.
2. It is under dash left of steering wheel as the driver sits.
3. smaller yellow block is the right one and is located one inch above another bigger yellow wire block which has a spring loaded connector.
Unplug the connector then Bend the paper clip to a U-shape and stick the paperclip in the 2 holes..
turn the car on, wait for the SRS light to go off, yank the paperclip out.
It'll light up again, shove the paperclip back in...
then it'll turn off. Yank it out. It'll then blink twice to tell you it's reset.
Don't worry about the timings...just do it as soon as you see the light change (and do it quick).
I cut a thin paperclip to about 2cm long, then bent it with needle nosed pliars so it looked like a staple. Then I just used the needle nosed pliars to push it in and out of the plug. Just be careful to shove it into the right side of the plug...the one side of the hole doesn't contact the metal.
(instructions copied from DareIL)