Engine Light Intermittent after Cambelt Change

Good evening guys. I was wondering if you could help me,

I seem to have the Engine Management Light come on for about 4-8 seconds then go off again, while doing under 40mph local town work. After a Cambelt and water pump change. (DW8 Engine)

I cannot read the fault as it goes off again and clears itself.

Anyone got any ideas?

Thankyou in advance!