Chevrolet 2008 Corvette Owner's Manual page 135

If the vehicle has lost power, the convertible top can
still be raised by releasing pressure on the hydraulic
pump, located under the passenger's side of the
tonneau cover, by using the following steps. The carpet
liner on the passenger's side must be pulled back to
access the hydraulic pump.
Manual operation of the power convertible top cannot
be attempted for five minutes from the last time the
convertible top button was pressed if the top is
not completely stowed, with the top down and the
tonneau latched, or closed, with the front top latch
locked in place, at the time the convertible top button
was released.
1. Open the tonneau cover by pulling the emergency
release cable.
The tonneau cover emergency release cable is
located behind the passenger's seat head restraint,
on the underside forward edge of the tonneau
cover. Also, see Hatch on page 2-13 for information
on the emergency trunk release handle.
Be careful when opening the tonneau cover by hand.
If the tonneau cover is opened quickly, damage can
occur to the hinging mechanism, which can prevent
proper operation of the convertible top.
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