A dashed line on your ECG display indicates that you have an invalid ECG signal in the wave sector.
You can either troubleshoot the currently selected lead to solve the problem (see
To replace a dashed line with a different lead:
In Wave Sector 1 - use the Lead Select button to cycle through available leads and select an
Use the Displayed Wave menu to select an appropriate lead.
NOTE: When using a 3-Lead cable, dashed lines will briefly occur with a change of the selected lead.
on page 184) or select a different lead.
4: ECG Monitoring
Table 50 "ECG