Help needed - repairing Mastech DMM

[bborisov567]

After measuring higher voltage than rated with my Mastech M890F occured the following problem - no matter in what range when i turn it on the value gradually starts going high and after a few seconds reaching "1.    " on the display. I replace the 7106 ic inside and C1, C2, C4, C5 but there is no change. Schematic is attached. Can you suggest where to look next?

[BreakingOhmsLaw]

I'd replace that TL062, probably the NPN Transistor in the output stage has gone leaky or short.
TL062 does not like inut voltages beyond it's power rails, so it might have seen overvoltage.

Also check if Vref is stable.

[bborisov567]

It turned out that both LM358s were blown and since they are getting power from the 7106 ic, they were shorting Vee to ground. After replacing them everything is working.