help with dilog tester

[sima24]

Hi all, i got a dilog 9083p tester a few weeks ago. Its been brilliant, but yesterday i was doin a zs test from living room light and everytime i pressed the test button it beeped and the screen jist displayed "fuse". Do zs test on the dining room light and gave me a good reading, so i know its not the actual fuse. Anyone had this happen or know what the cause could be?
Thanks in advance

 

[MarkieSparkie]

Try cleaning the fuse end caps and fuse holder contacts with isopropyl alcohol or switch cleaner, if they are badly tarnished use a mild abrasive first, if this intermittent condition persists fit a new fuse.