An apparatus, a method and a computer program product are provided for conserving energy during functional mode of a processor by disabling the scan chain. By inserting logic gating into the scan chain it is possible to disable the scan chain during the processor's functional mode. During functional mode the scan out port of the latch bit in a scan chain toggles, which leads to unnecessary energy consumption. By gating scan control signals and the scan out port of a latch bit, the scan chain segment between latch bits can be disconnected. Therefore, the scan control signals can disable the scan chain during functional mode.