HP Rp3000 - Point of Sale System Troubleshooting Manual page 20

Sliding door that covers the optical drive will not open.
Cause
The sliding door is locked.
Not getting the correct power on the COM port.
Cause
COM port jumpers are not set correctly.
14 Chapter 2 Troubleshooting Without Diagnostics
Solution
Use the provided key to unlock the door then slide the door
down.
Solution
See "Configuring Power to a Serial Port" in the Hardware
Reference Guide for instructions on setting the COM port
jumpers for power.
ENWW