Pioneer AVIC S1 - Automotive GPS Receiver Operation Manual page 27

Frame by frame playback and slow motion playback
Push the control stick up while the Operation mode switch is set to "DVD".
Reverse frame by frame playback and reverse slow motion playback
(in case of XDV-P9 and XDV-P90)
You cannot do this with the Remote Control included with AVIC-9DVD. However, you can
operate this function using the Remote Control included with the DVD player or the AV Head
Unit.
Switching DVD information screen (Built-in DVD player only)
Press the Display button (CANCEL ROUTE button) while the Operation mode switch is set
to "DVD". The display switches over as you press the button.
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