HP_UNEQ alarm indicates that the high order channel is not loaded, the actual C2 byte is "0x00".

When you view the alarm in the network management, select the alarm, and the alarm parameters will be displayed in the "Alarm Details". The format of alarm parameters is "Alarm Parameters (hexadecimal): Parameter 1 Parameter 2...Parameter n". See the following table for the meaning of each parameter.

It will cause the service of this channel to be interrupted, and at the same time, it will report HP_RDI back to the opposite end station.

Note: If there is no corresponding fault phenomenon for the probable cause, or the fault phenomenon is not listed in this section, follow the recommended sequence of operations in the "Processing Procedure". The common faults generated by the alarm HP_UNEQ are shown in Table 1.

Table 1 Description of alarm HP_UNEQ reported phenomena

Common Failure Phenomena		Corresponding cause
Alarm HP_UNEQ is reported on the corresponding channels of network elements along the upstream route.		Cause 1: No service is configured on the upstream network element.

The possible causes of the alarm HP_UNEQ are listed below:

• Cause 1: The service is not configured for the network elements along the upstream.
• Cause 2: The C2 byte to be sent from the terminating site is "0x00", and the service passthrough network elements are set to overhead passthrough.
• Cause 3: The C2 byte to be sent at the termination site is not "0x00", and the service passthrough network element sets overhead termination and configures the C2 byte to be sent as "0x00".