IBM 6611 Pocket Manual page 84

Before starting the Model 170 for operation, set the
key mode switch to Normal. This permits the Model
170 software to load after the POST has completed.
If the Model 170 is not operating correctly, contact
your IBM service representative. In the United
States, call 1-800-IBM-SERV. In other countries,
contact your IBM marketing representative for the
service phone number.
Chapter 8. Using the Model 170
8-3