First of all thank you for letting join Hi to all.

[ArvindT]

I have DVM ISO- TECH IDM93N
AC range not working just reads 1499.
DC range reads 1 . on all ranges
DC current not giving correct values compared to another DVM
Resistance range reads 1 . and floating readings
Diode range reads 1.
Both fuses okay.

Help required to fix the problem.

 

[M.Joshi]

Have you opened the meter up to inspect the PCB and components?

Do you know which microcontroller is used for that meter?

It may help you in finding a datasheet/schematic to fault find.