Prius died on the way home...

If the brake system detects that it has failed, either factually
or erroneously, it's got a little !loud! beeper mounted next to
it that it sounds to warn you that you've lost ABS and other
braking features. If you look up past the brake pedal under the
dash, you'll see the brake computer with a bunch of connectors, and
a little white box with a small round grille in one side. That's
a dedicated noiser for the brake system.
.
_H*

 

P0607 Control Module Performance

circuit description: DTC 0607 is stored when an internal abnormality of the hybrid vehicle control ECU is detected.

detecting condition: the hybrid vehicle ECU has a supervisory CPU and a control CPU inside. this trouble code is output when input STP signals to each CPU are different for 0.15 seconds or more.
trouble area: hybrid vehicle ECU
hint: if DTC P0607 is detected while the cruise control is in operation, the system clears the stored vehicle speed in the hybrid vehicle control ECU and cancels the cruise control operation. at the same time, the CRUISE main indicator light blinks to inform the driver of the malfunction. when this trouble code is detected, fail-safe remains on until the power switch si turned off.

inspection procedure: replace hybrid vehicle control ECU