Thanks Doc, i was hoping that was the case, i would have thought Tesla would be the first to go fly by wire brakes/steering maybe on their truck.

If we do go down this road i know it will be a learning cuve for me as i maintain my own brakes to what i hope is a high standard, will be the first venture into working on an EPB too, i believe there's a proper method to safely shut the system down before working on it, same as with Merc's SBS system, hopefully my current version of Techstream covers the Prius models in question.

I would have thought a direct connection to the master cylinder, as shown on the unit in the link, would mean even if all electric power was lost shoving the brake pedal would still operate the brakes but obviously without an assistance.

Also in the event of a panic stop when the driver jumps on the brakes isn't the regen system 'sidelined' as it were allowing the standard hydraulic brakes to do what they have always done.

Not nit picking here, just making sure there's a standard pretty well fail safe system backing things up in case of complete eletrical failure...many years ago driving my sisters Wartburg Knight i experienced complete brake failure (most likely boiled or poor quality fluid, changed fluid and it never happened again), fortunately the superb park brake thanks to rear drums stopped the car effectively, belt and braces for me.

Edited by gordonbennet on 07/09/2025 at 15:48

You’ve definitely got a mechanical link to the hydraulic system if the electric pump fails . Similar to driving with no vacuum servo assistance. Electric hydraulic brakes are nothing new . Ford Granada / Scorpio models had it in the 80s . The MB Sbc system was similar but had timed out functionality. Audi now have similar issues with their larger models. The abs system has a limited number of brake applications before the complete module needs replacement. Not a cheap job .

Toyota don't have a counter system in place, quite ludicrous that MB and Audi should have done so IMO though MB dropped the SBC system in short enough order.

The pressure pump is what will give trouble on the Toyota set up if anything will, thankfully very rare to do so and chances are it will be at least 25 years old before needing work but www.robsonandfrancisrewinds.co.uk/ can rebuild said motor itself if needed, which is just as well because a new combined unit is in the £thousands and far as i'm aware Toyota will only sell complete units, whether the more compact unit fitted to Prius can be similarly separated and overhauled by a specialist haven't a clue.