Brake actuator problem after replaced brake pipes

Hi all,

My 2007 Prius had a rear brake hose failure at the weekend, and since they quoted reasonably, I foolishly took it to the local Toyota dealership.

(The symptoms were extended booster pump run, followed by VSC/ABS/Brake lights on, braking going into fallback hydraulic mode, a persistent continuous beep from the ECU and, diagnostically, a big puddle of brake fluid at the rear wheel. BUT, suspiciously, no fault codes over OBD)

After replacing the hose, they said they couldn't contact the brake actuator ECU to bleed the rear brakes, and that the beeping sound (which they said they'd never heard before) was continuing. And they asked for £210 for 2 hours to "invetigate", which I stupidly said "yes" to without thinking about it more myself.

So, is this likely to be a wiring fault (inability to connect to the ECU) or could the brake pipe failure somehow have precipitated a fault in the actuator ECU?

And does anyone know if the hybrid system communication goes over the same CANbus wires that the OBD would be probing? If so that would make a simple wiring fault seem unlikely.

Sigh.

Thanks!

 

Turns out that, yes the CAN has a very intermittent connection, though the BEAN is still fine, and most signals are on the BEAN. The dealership got connection to the CAN by connecting directly to the ECU, and after some worries about the brake pump potentially being faulty, everything seems fine now except for the intermittent connection on the CAN. So I'll have to try and track that down at some point, but for the moment we have a functioning car again. Phew