Mercedes-Benz SLK 350 Operator's Manual page 222

Controls in detail
Audio system
Talking with two callers at the same
time
If you wish to receive or place another call
during an already active call, you can
accept or place the second call and switch
between the callers or combine them into
one call. Note that the features described
here are depending on availability from
your mobile phone service provider.
Placing/accepting a second call
Place new call by entering
telephone number manually.
Press s button.
You are connected to the second
caller; the first caller is kept on
hold.
or
Press s button to accept a
second call.
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You will be notified of the second call
acoustically, but you will not see this in
the display.
You are connected with the second
caller; the first caller is kept on hold.
Switching between calls
Press 2 and s buttons.
This switches between the calls.
The non-active call is kept on hold.
Terminating a call
Press t button.
The current call is terminated. You
are again connected with the caller
previously placed on hold.
Combining two calls
Press 3 and s buttons.
The calls are combined into one
call.
Terminating a combined call
Press t button.
The connection to both callers is
terminated.