Keysight 34980A Slope Convergence DMM issue

[a100man]

Hi,

I have a Keysight 34980A, and the self-test fails with only error 604 "Self-test: A/D slope convergence". In DMM mode, it reads 0.0V constantly, which I suspect is because the DMM is not reading at all due to the error. I know internally this DMM is similar to the 34970 and the 34401 and there has been some discussion on repairing those devices. Since the 604 is the only error I'm getting, I'm wondering if anyone has any ideas for a particular component I should check?

Thanks

[m k]

Hook a scope to A/D input and check if there is anything alive.