1
Troubleshooting Guide
Model 478DA (D-15)
Single Intercom System
Introduction
The Model 478DA is a single-channel intercom system that is used for point-to-point communication applications.
The system includes a visible/audible presence alert and the capability of multiple units communicating with the same
loudspeaker.
Problem Isolation Procedure
Use the troubleshooting table on the following pages to help isolate the problem:
1. Start at the top of the table and work down to the bottom.
2. For each symptom listed, determine if it applies to the situation.
3. If a symptom does apply, check (
ü
) the box adjacent to the symptom.
4. Read across the table to the possible causes and corrections listed in the middle and right columns.
5. Investigate these possible causes and implement the corrections. Possible causes are listed in the order in which
they are most likely to occur.
If none of the possible causes and corrections applies to the situation, call 3M Media InTouch and review the
"checked" symptoms with the technical support staff.
