[2] STS-123 delivered the pressurized section of the Japanese Experiment Logistics Module (ELM-PS) as well as the Special Purpose Dexterous Manipulator (SPDM) to the International Space Station.

[4] On February 11, 2008, Endeavour was "rolled over" to the Vehicle Assembly Building in preparation for mating with the external tank and solid rocket boosters.

[13] After docking the pallet carrying Dextre was moved to the Payload ORU Accommodation (POA) of the Mobile Base Station (MBS) by Canadarm2.

[14] Engineers on the ground tried a software patch, though later suspected a design flaw in Dextre's temporary power cable caused the issue.

[16] The crew spent time outfitting the Japanese Logistics Module, transferring supplies and equipment into it from Space Shuttle Endeavour.

Engineers expressed confidence that this issue would be resolved Rick Linnehan and Robert Behnken ended their day by "camping out" in the station's Quest Airlock.

Among other tasks, they also checked out and calibrated Dextre's end effector and attached critical spare parts to an External Stowage Platform.

[20] In a day highlighted by robotics activity, Dextre was attached to a power and data grapple fixture located on the U.S. laboratory Destiny.

Before going to sleep, Mission Specialists Robert L. Behnken and Mike Foreman entered the station's Quest airlock for the standard "camp out".

[22] Mission Specialists Robert L. Behnken and Mike Foreman completed the fourth STS-123 spacewalk at 04:28 UTC, spending six hours and 24 minutes on the excursion.

The two shuttle crew members replaced a failed Remote Power Control Module — essentially a circuit breaker — on the station's truss.

With Mission Specialist Rick Linnehan coordinating their activities from inside the orbiting complex, the spacewalkers also tested a repair method for damaged heat resistant tiles on the Space Shuttle.

Gorie, Johnson, and Doi surveyed the orbiter's wings and nose cap to ensure that no damage had occurred to the tiles that protect Endeavour from the heat of reentry.

Foreman and Behnken hooked an extra-long power cord to the inspection pole, to keep its lasers and cameras warm for the next two months, then secured the boom to the outside of the space station.

NASA hopes to have a plan for dealing with the jammed joint by the end of the month, space station flight director Dana Weigel said.

Afterward, the crews wrapped up transfers of equipment and supplies between Endeavour and the station, and out the tools needed for undocking and subsequent activities.

Early in their day, the crew members performed a test of the thrusters that will be used to position the orbiter for re-entry and the control surfaces for its flight through the atmosphere.

The STS-123 astronauts also set up the recumbent seat for Mission Specialist Léopold Eyharts, who joined the crew of Endeavour on the International Space Station.

The exhaust produced by the Hydrazine Gas Generator APUs on either side of Endeavour's tail fin created concern among some observers that something was amiss, as it appeared more pronounced than usual in NASA's visual light cameras.

[30] The hydraulic power is needed for the shuttle's rudder/speed brake, elevons, body flap and landing gear during descent, and for the main engine nozzles' gimballing during ascent.