Help with rear window heater switch

[vectraasra]

When i switch it on the switch doesent light. Relay clicks.
1st i changed switch no change.
2nd changed 30amp fuse.
3rd changed blue relay.
4th changed multi-timer control unit.
Any help am new to car electrics, where should i be looking i have a digital mulit-meter ony 10amp.
Any suggestions please

[oberlisc]

You say the switch does not light up, but does the rear window demist.

[vectraasra]

no it just makes the relay click confusing...?