Lexmark Optra C Service Manual page 124

5045-001
Service Technician Adjustment
Initialize as the service technician adjustment mode, and that
function operates instead of the density adjustment function. At this
time, the "Bk" indicator flashes to indicate the service technician
adjustment function if the panel is not OFF.
1. Press the power switch while holding down the TEST PRINT
key to initialize the service technician adjustment mode.
2. Press the COLOR SELECT key and select an adjustment item.
The LEDs for the currently selected adjustment item and that
adjustment value flash. The correspondence between the
COLOR SELECT LEDs and each adjustment item is as follows.
3-19