Cisco ONS 15454 Series Multiservice Provisioning Platforms

Field Notice 12821: Cisco ONS 15454 Fan Tray Failures

Revised: May 4, 2001

July 10, 2000

Products Affected


Top Assembly

Printed Circuit Assembly


HW Rev.

Part Number


Part Number







Compatible with 15454-SA-NEBS3 only




A0. B0, D0, D1



Capatible with 15454-SA-NEB3E only.


Problem Description

In some fan tray assemblies, the wires connecting the fan control board to the individual fans have been pinched in assembly and may cause the Asynchronous Transfer Mode Interface Processor(AIP) board fuses to fail. This failure has been seen in several new turn-ups and should be immediately apparent at power on. When a faulty fan tray assembly is inserted into a shelf, that fan tray may cause a failure of the AIP board on the shelf.


This issue was detected during a customer turn-up. A defect in assembly was detected during failure analysis.

Problem Symptoms

If a new fan tray assembly, with this assembly defect present, is inserted into a powered node, the fan tray may fail and can cause the fuses of the AIP board to fail. This will immediately be apparent as the fan tray assembly will not function. However, the LED on the fan tray assembly will continue to operate, but will display garbled information.


If you encounter a failed fan tray, please contact the Technical Assistance Center immediately to request an RMA.

Note:?Do not place a failed fan tray into other shelves as this will cause additional AIP boards to fail

Any fan trays already in service and operating are not affected by this defect and do not require replacement.

Cisco has implemented a High Pot test to ensure circuit integrity through the Fan Tray Assembly. This test will ensure that all fan trays that ship will be free from this defect.

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: