CAUTION: Many repairs may only be done by a certified service technician. You 
should only perform troubleshooting and simple repairs as authorized in your 
product documentation, or as directed by the online or telephone service and 
support team. Damage due to servicing that is not authorized by Dell is not 
covered by your warranty. Read and follow the safety instructions that came with 
the product. 
1  It is recommended to turn off the system, including any attached 
peripherals, and disconnect the system from the electrical outlet. 
2  Remove all the hard drives. See “Removing a Hard-Drive Carrier” on 
page 135. 
3  Open the system. See “Opening the System” on page 218. 
4  Disconnect all the cables from the backplane. See Figure 5-5 for 2.5-
inch hard drives.  
Note the routing of the cable on the chassis as you remove them from 
the system. You must route these cables properly when you replace 
them to prevent the cables from being pinched or crimped. 
5  Disconnect front panel cables from the power distribution board. See 
Figure 3-96 or Figure 3-99. 
Note the routing of the cable on the chassis as you remove them from 
the system. You must route these cables properly when you replace 
them to prevent the cables from being pinched or crimped. 
6  Remove the hard drive cage from the chassis. See Figure 3-84. 
7  Disconnect the cable from the sensor board assembly. See Figure 3-99.