Self-diagnostics function constantly logs "EQP BUSY" alarms with "NO TRUNK SEIZE ACK" with the console display showing the following:

A11 0060 NO TRK SEIZE ACK 08/04
I use the fuinction key code to clear the alarm, then the next system check logs it again. We have 7 incomming lines, but only 3 "hold" buttons on the console. I called a recorded message number 3 times placing all 3 on hold, then used a cell phone to call the main business line, and it alarmed out with the busy out. Can anyone tell me whats going on with this thing? UPDATE!..TRUNK 60, IN SLOT 08, STEP 01. WHERE DO I LOOK FOR THIS AND WHAT DO I DO? THANX!!!