rear heated window fault

[graham.green]

my 1997 c180 has a rear heated window problem the switch is not lighting up and screen not clearing . i have checked the fuse and this seems to be ok .?
i have recently changed the relay for the indicators as these were playing up,this is a multi function relay not sure if this is the problem without fitting the old one back in as the rear heater was working prior to fitting this. any advise ??????

 

[wireman]

It is the same relay.

 

[graham.green]

rear heated window

thanks for the info i try changing back to the old relay if it works ,iwill take the relay i purchased back . cheers graham