In 1992, six 4-car sets were reassigned to Okayama Depot.
At this time, the lavatories were upgraded and the Sunliner livery appeared, and some of these sets operated at speeds of 115 km/h (70 mph).
In 1999, fare collection boxes were installed to support driver-only operation without a conductor on board.
These consists were designated as:
E1: KuHa117-9  – MoHa117-18 – MoHa116-18 – KuHa116-9
E2: KuHa117-11 – MoHa117-22 – MoHa116-22 – KuHa116-11
E3: KuHa117-13 – MoHa117-26 – MoHa116-26 – KuHa116-13
E4: KuHa117-15 – MoHa117-30 – MoHa116-30 – KuHa116-15
E5: KuHa117-17 – MoHa117-34 – MoHa116-34 – KuHa116-17
E6: KuHa117-19 – MoHa117-38 – MoHa116-38 – KuHa116-19
Later, three 4-car sets were borrowed from the Miyahara Depot and designated E11, E12, and E13.
These were used in the region on local services and also served as the primary units for Sunliner rapid service.
These were run as far north as the Yonago area for special services during periods of high ridership.
100 sub-series cars at the Okayama Depot without upgraded lavatories were mothballed at the Gotō Depot in Yonago until reassignment to Shimonoseki in October 2005.

3500 sub-series renumbering
MoHa117/116-17, 21, 23, 25, 27, 29, 31, 33, 35, 37, 39, 303, 315, 316 → MoHa115/114-3501 – 3514
In 1992, six 4-car sets were reassigned to Okayama Depot. At this time, the lavatories were upgraded and the Sunliner livery appeared, and some of these sets operated at speeds of 115 km/h (70 mph). In 1999, fare collection boxes were installed to support driver-only operation without a conductor on board. These consists were designated as:
E1: KuHa117-9  – MoHa117-18 – MoHa116-18 – KuHa116-9
E2: KuHa117-11 – MoHa117-22 – MoHa116-22 – KuHa116-11
E3: KuHa117-13 – MoHa117-26 – MoHa116-26 – KuHa116-13
E4: KuHa117-15 – MoHa117-30 – MoHa116-30 – KuHa116-15
E5: KuHa117-17 – MoHa117-34 – MoHa116-34 – KuHa116-17
E6: KuHa117-19 – MoHa117-38 – MoHa116-38 – KuHa116-19
Later, three 4-car sets were borrowed from the Miyahara Depot and designated E11, E12, and E13. These were used in the region on local services and also served as the primary units for Sunliner rapid service. These were run as far north as the Yonago area for special services during periods of high ridership. 100 sub-series cars at the Okayama Depot without upgraded lavatories were mothballed at the Gotō Depot in Yonago until reassignment to Shimonoseki in October 2005.
3500 sub-series renumbering
MoHa117/116-17, 21, 23, 25, 27, 29, 31, 33, 35, 37, 39, 303, 315, 316 → MoHa115/114-3501 – 3514
117 series