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changing fans and psu in 4500x fiber switch

Level 1
Level 1

I have a 4500x TOR switch that has fans and power supplies that push air from front to back. I've purchased 2 new power supplies and 5 fans that push the air back to front. 


When I put in the new power supplies and fans the switch never turns on the fans, and then it gets almost done booting and says that there are no supported power supplies and shuts off.


Is there any commands I have to run to switch the PSU and fans out? We have another 4500x switch and didn't have this issue when we changed them.


Thank you

1 Accepted Solution

Accepted Solutions

That model (WS-C4500X-16SFP+) is front-to-back only. You can't change that.


View solution in original post

7 Replies 7

Reza Sharifi
Hall of Fame
Hall of Fame

There is no command to turn on the PSU or the fans. When you power up the switch, they all start. What are the part numbers for the PSUs and the FANs?


Fans are C4KX-FAN-F


Power supplies are C4KX-PWR-750AC-F


We are replacing the ones that end in -R


Thank you

Leo Laohoo
Hall of Fame
Hall of Fame

What firmware is the switch on?

Here is the show version.


4500x_Corp#show version
Cisco IOS Software, IOS-XE Software, Catalyst 4500 L3 Switch Software (cat4500e -UNIVERSALK9-M), Version 03.10.01.E RELEASE SOFTWARE (fc4)
Technical Support:
Copyright (c) 1986-2018 by Cisco Systems, Inc.
Compiled Tue 06-Mar-18 10:24 by prod_rel_team


Cisco IOS-XE software, Copyright (c) 2005-2015 by cisco Systems, Inc.
All rights reserved. Certain components of Cisco IOS-XE software are
licensed under the GNU General Public License ("GPL") Version 2.0. The
software code licensed under GPL Version 2.0 is free software that comes
with ABSOLUTELY NO WARRANTY. You can redistribute and/or modify such
GPL code under the terms of GPL Version 2.0.
( For more details, see the
documentation or "License Notice" file accompanying the IOS-XE software,
or the applicable URL provided on the flyer accompanying the IOS-XE


ROM: 15.0(1r)SG10
4500x_Corp uptime is 22 hours, 24 minutes
System returned to ROM by power-on
System image file is "flash1:unknown"
Jawa Revision 2, Winter Revision 0x0.0x41


Not sure what model you have, but have a look at table-1 in this link:


I have this model




Does that mean you can't change out the fans and PSU?

That model (WS-C4500X-16SFP+) is front-to-back only. You can't change that.


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