Just replaced actuator and accumulator now I'm getting a code c1242. I can't find much information about this. Any help would be greatly appreciated.
I just googled that code and probably found what you already know. In a Toyota Prius, a DTC C1242 code indicates an "Open in IG1 / IG2 Power Source Circuit" issue, typically related to the ABS, BA, TRC, or VSC systems, requiring inspection and repair of the relevant wiring or connectors. Google's help points toward checking the wiring connections and fuses. I recently replaced the master cylinder on my 2012, but left the pump alone. I remember the harness connection for the master cylinder was a little strange. Are you sure that is seated well and locked down? I assume you were not able to do the bleed procedure
Did you perform system initialization after replacement? https://attachments.priuschat.com/attachment-files/2022/05/221890_Electronically_controlled_brake_system.pdf
@Frontporch I double checked the harness connections and they are seated well. I was able to perform the bleeding procedure. I'm thinking it might be my 12v battery.
@MAX2 Do I need to perform system initialization if I completed the bleeding process? Do you think it could be my 12v battery?
The initialization procedure is set by the manufacturer. This is due to the fact that the replaceable parts do not have absolutely identical parameters. There are differences somewhere and they need to be aligned for a given electrical system of a specific car. The 12V battery must be charged and have a reserve capacity so as not to interrupt the procedure in the middle. A lot depends on the 12V battery. When it is discharged, there may be many unexplained errors in different systems.
Google is great, but: Toyota Service Information and Where To Find It | PriusChat The car's skid-control ECU gets power redundantly (when the car is IG-ON) at two terminals: IG1 (pin 16 on its connector, a black wire, at least in 2010), and IG2 (pin 12, a beige wire, at least in 2010). The IG1 supply comes via the 10 amp "ECU-IG No. 2" fuse, while the IG2 supply comes via the 10 amp "IGN" fuse. When you use a scan tool that can show freeze frames for trouble codes, the C1242 code has two different "INF codes" that can show up in the freeze frame. INF 111 means the skid ECU was getting power (9.5 V or more) on IG2 for four seconds or more while not getting power (well, less than 3.5 V) on IG1. INF 112 means the reverse: the ECU was getting power (>= 9.5 V) on IG1, for four seconds or more, while not getting power (< 3.5 V) on IG2. So if you have a way of getting that INF code, it cuts your troubleshooting workload about in half by telling you which one of those circuits you should be poking at.
Oh, sorry, you did upload Techstream screens with the INF code, I just didn't spot it up there. In your first attachment, see the top row "Detailed Freeze DTC 112", where 112 (as in post #9) means that IG1 was getting decent power and IG2 was not. In your second attachment, you can see that IG1 Voltage Value was 13.80, while IG2 Voltage Value was, um, 0.31 volts. If I were a brake ECU, I'd set a code for that too. And C1242 INF 112 would be the code I would set. You need to find out why such a pathetic voltage is arriving at the IG2 (pin 12, beige wire) of the brake ECU. That circuit passes through the 10-amp "IGN" fuse, and otherwise travels as you see in the wiring diagram: Toyota Service Information and Where To Find It | PriusChat
