Cisco 12000 Series Routers

Field Notice: Cisco 12406 CSC Revision A0 Improper Clock Termination

Updated December 17, 2002
April 9, 2002

Products Affected

Product Top Assembly Printed Circuit Assembly
Part Number Rev. Part Number Rev.
GSR6-CSC=   800-12096-01   A0   73-5702-02   A0  
GSR6-CSC/R   800-12096-01   A0   73-5702-02   A0  

Problem Description

Cisco 12406 CSC revision A0 line cards may experience the following problems:

  1. Fail over time between operational CSC to redundant CSC may not occur, or may take up to 13 seconds.
  2. CSCs may experience parity errors during the interval between CSC failure and fail over.


GSR6-CSC revision A0 cards generate invalid clock signal levels due to improperly placed termination resistors. This will affect both the operational and redundant CSC, resulting in CSC fail over not occuring or taking up to 13 seconds to complete.

The following error messages can be indicitive of this problem and will result after the CSC fails:

  • %FABRIC-3-LOS: LOS for slot was detected.
  • %FABRIC-3-CRC: Switch card
  • %FABRIC-3-PARITYERR: To Fabric parity error was detected. Grant parity error Data = 0x2.

Problem Symptoms

GSR6-CSC cards fails to roll to the redundant CSC.


Cisco would like all customers with GSR6-CSC revision A cards to use the upgrade form below to request a CSC. "How to identify hardware revision" instructions are below.

Note: All 12406 CSC cards manufactured after April 2, 2002 do not have this problem.

This upgrade program will be available to customers through March 1, 2003.

How To Identify Hardware Levels

Execute the show diag command and look at MAIN. If the hardware part number is "800-12096-01 rev A 0" or lower it is affected by this field notice.


 csa-qd1#show diag 17
 SLOT 17 (CSC 1 ): Clock Scheduler Card(6) OC-192
 MAIN: type 29, 800-12096-01 rev A0 dev 0
 HW config: 0x00 SW key: 00-00-00
 PCA: 73-5702-02 rev A0 ver 2
 HW version 1.0 S/N CAB0533K2DR
Note: 800 level revision B0 CSCs are not affected by this      problem. 

Upgrade Program

GSR6 CSC Clock signal termination

If you have any questions concerning the upgrade program, you can e-mail

Note: Fields marked with an asterisk (*) are required fields.

Company Information
*ZIP/Postal Code
Product *Quantity
Contact Information
*First Name
*Last Name
*Phone 1 Ext.
Fax 1 Ext.
*Internet E-Mail
Please use the following format:
*Upgrade Order Reference Number
Please provide a number that you can use when inquiring about order status
*Serial Numbers of Affected Units 2
1 For phone and fax, include 011 and the country code outside North America.

2 When entering more than one serial number in the serial number text entry field, be sure to type a comma between each serial number to separate them.

For More Information

If you require further assistance, or if you have any further questions regarding this field notice, please contact the Cisco Systems Technical Assistance Center (TAC) by one of the following methods: