How can I fix my SRS warning light on 2002 Ford Escort 1.6 LX?

The SRS warning light on my M plate Ford Escort 1.6 LX is having a tizzy. When you turn the ignition key to the II position the light ccomes on for a few seconds and the goes out just as it should to indicate that there are no faults in the SRS system. However, once out on the road it sometimes starts to flash intermittently. Any ideas about what is causing this and how do I get at the dash lights to check the wiring?