Why does the internal resistance measurement no longer work

This may be due to incorrect use of the Kelvin probes supplied.

The Kelvin probes are to be used exclusively for measuring the internal resistance of battery blocks up to 24V voltage.

The background to this is the connection of the probes to the P+ measurement input (current-carrying path) which is fused at 24V.

If the Kelvin probes are used in conjunction with higher voltages, an internal fuse is triggered and the internal resistance measurement will no longer function permanently (service case).

The multimeter test probes supplied with the device must be used for all voltages above 24V.