True Fitness Treadmill ES9.0 + ES7.0 Owner's Manual page 69

The following service messages will be displayed as they occur,
as well as for the subsequent six safety key insertions. These
messages will be displayed until a key is pressed. Every time these
messages are displayed, a tone will sound twice.
S1:LUBE
This message is displayed when lubrication of the
deck is recommended.
S2:CLEAN
This message is displayed every 500 miles. Prompt
to clean treadmill.
S3:MOTOR This message is displayed every 2500 hours.
Prompt to check motor brushes.
Service Messages
Chapter Nine: Care and Maintenance
ES Treadmills Owner's Guide
Diagnostics
Service
Messages
69