A driver needs to display their current 24 hour period and the previous cycle length of logs at a roadside inspection. They must have the complete information either on the ELD or on paper.
If there is no way to access any of your current logs from the ELD, current 24 hour period and the previous cycle length (i.e. 7 or 8 days depending on rule-set) need to be reconstructed on paper.
When an ELD fails to work properly the driver is required to use paper logs and start logging on paper. They can only do this for 8 days before the ELD malfunction should be fixed. Drivers are required to keep some logging paper in the cab specifically for this purpose.