The manual doesn’t mention anything about 2 beeps.
5.11 DCS100 Audible Sounds
The DCS100 uses several beeps and clicks that can be used as diagnostic tools
that help you debug a number of conditions.
Table II: DCS100 AUDIBLE SOUNDS
Sound Meaning
1 Beep DCS100 has powered on successfully or has sent
a programming command.
3 Beeps A loco address has been “purged” due to non -use.
This is informational only. Refer to the DCS100
Option Set Up Section for information on
customizing loco address purging.
4 Beeps Booster short circuit shutdown. Fault Alarm
6 Beeps Command station already present in system.
When two command stations are operating on the
same system, you may experience unexpected
results.
7 Beeps DCS100 CMOS battery lo w condition. Battery
should be replaced as soon as possible. See
Section 5.14 for CMOS battery replacement
instructions.
8 Beeps Memory ECC/checksum fail. This indicates that
the local CMOS memory has been corrupted and
was reset automatically. This i s a technical
diagnostic.
9 Beeps DCS100 transmit failure, there is a device
blocking proper message action on LocoNet.
16 Beeps Software timeout failure. No action is required,
the unit will resume operation.