Is the Mini-VCI Cable and Techstream Necessary?

Yes. Techstream or an equivalently capable scan tool that has bidirectional capabilities is required.

Despite what you may have read you will not be able to bleed the actuator properly nor set some parameters without a scan tool.

Furthermore, if you are going to use a third-party cable (VCI–vehicle communication interface), make sure to buy a decent one as some of the cheap Mini-VCI cables are too unstable and will lose communication during the process which is very undesirable.

A discussion that includes such scanners is here: Gen2 OBD2 app review.

 

Lots of choices, Vxdiag, Tactrix Openport, Mini-vci

Mini VCI and Techstream | PriusChat

Tactrix Openport 2.0
What OEM J2534 software does the Openport 2.0 work with?

https://www.obdii365.com/search/?q=toyota&DirID=

 

I was not able to make dealer tec bleed my 09 brakes yet. Have great brakes and vac works wen traction breaks. I feel no air res is on F line never budges. Wen pumps pumping etc . I've just left it alone . I'd like to know why this is so. I also don't use tec to set TPMS sensors. Just use tire store wand . No need serial numbers of TPMS sensors anymore . Don't know why . TPMS equipment evolved I guess . Why would a tech need to type in numbers . Wen new tool detects these numbers . I guess

 

Not sure that you're contributing to the discussion, you're talking to yourself most of the time.

 

Like I say I tried this several times talking to whoever and could not get the stream to do the brake bleeding like described by all these folks same with the TPMS sensors lots of pushing and entering numbers and hoping and whatever fast forward to the tire store where my buddy says ah you don't even need to fool with any of that pulls out this little yellow wand looking thing hits the button and it beeps He goes around to each wheel waves it over the nonsense the light in the car goes off and we go back in the shop and talk nothing else to do what's so hard about that for other companies I guess that tech wasn't available when stream was put online

 

Everything else on the tough book works on stream just these two things so far that we've tried to do and it's not kept us from doing anything The two is fine The three I have not replaced any of the brake business yet so I haven't had a chance to see if it will bleed the three which I'm sure it probably will

 

Techstream is specific to Toyota, Lexus, and Scion but it does have a generic mode that will give you basic ECM info at about the same level as a $50 HF reader.

Third-party readers will need a Toyota PID (parameter ID) file for Prius (minimum) and maybe other "goodies" (technical term) in order to know how to command the brake system to do the actuator bleed and set parameters.