Pioneer AVIC-S1 - Manual (Page 20)

Redial
Tap the Redial button on the Bluetooth HF Phone main screen to dial
the last number you called or received.
Mute
Cancel
2.5 Operations During a Call
During a call, four functions are available:
End Mute Switch to
mobile phone.
z
If you need to input other numbers, such as an extension number, tap
to open the keypad and tap the digits. The keypad will close when you tap
the button again or when there has been no input for 5 seconds.
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