Bosch Integral TS13 Operating Instructions Manual page 98

If in doubt, look it up
If something goes wrong A
Telephone does not react to input
Perhaps you have entered an incorrect PIN three times consecutively.
The telephone is then blocked for 15 minutes.
A function is not performed
Your BOSCH TELECOM service representative may need to enable this function.
Functions which have to be enabled are tagged with -.
Telephone prematurely aborts programming
You may not have pressed a key during the last 60 seconds. This will cancel all
programming procedures.
Programming is also canceled when you answer a call.
Call diversion is not performed
Check whether the defined call diversion has been activated.
Additional digits cannot be dialed for a call number that was dialed with code
dialing
Postdialing is probably blocked.
A call is displayed on the screen, but your phone does not ring
Check whether the ringing tone has been deactivated (in the "Do not disturb"
menu).
No entries in the call list
The call list has probably been deactivated. Reactivate the call list in the
"Specifications" menu.
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