2005 Prius with 300k miles, DTC c1319 problem

The "changeover solenoid" is another name for the stroke simulator solenoid. The purpose of that part is to make the brake pedal feel normal when the pedal is depressed and regen braking is in effect.

As you know by reference to the repair manual, that DTC is caused by one of three possibilities: the stroke sensor, the skid control ECU or the associated wiring harness. The repair manual provides info about how to narrow down the problem by measuring resistance across the sensor and verifying that the proper voltage is present at the sensor and the ECU. I suggest that you follow the troubleshooting steps.

 

I have replaced three Skid Control ECU's. U codes often appear with their failure. U codes relate to communication errors. The Skid Control ECU can affect regeneration. Three nuts hold the ECU in place. The top nut is a bear to get to. With your eyes next to the gas pedal the nut is barely visible. I use a deep 10 mm 1/4" drive socket, then a 1/4" U joint, and about a 18" extension. 3/8" drive sockets and U joints will not work, they are too big. It also helps to put some masking tape on the U joint to slow it down. Once you get the socket on the nut it will spin off with out too much trouble. No trim panels need to be removed. Techstream has a couple of calibration steps that are needed after replacement.

Brad

 

I think the skid control ECU's should all be recalled. But that's not my call. I do remember reading something about Toyota repairing the ECU's. Do you have Techstream? Did you get a sub or inf code? The front right brake not working is a huge clue of what is wrong with your car. Techstream has several tests and resets available in the ABS section. It would be worthwhile to take a look. Since you have already paid for the ECU I would recommend putting it in.

Brad

 

Who knows? But you do know that something is not working right there. It could be just a plain old stuck caliper. Or it could be caused by the incredibly complicated Prius braking system. It's a good place to start looking. How about jacking the right front wheel up. Have the car running in neutral. With a helper stepping on the brakes try to turn the wheel by hand. Or get both front wheels off the ground and see if the brakes will stop each of them with the car in drive. The ABS would not be happy about having one wheel it could not control. Maybe a stuck caliper is frustrating the heck out of the computers? Maybe the computers are sending jiberish to the caliper?

Do you have Techstream?

 

Why? What clues has the car given you? Just to rule it out you could try pulling the caliper off and retracting the piston with a c clamp.

Here is a list of codes one failed skid control ECU produced. U0100, U0129, C1310,U0073, U0293,C1259, and U0121. That is very different from what you are seeing.

This car lost almost all braking function. U0129,C0200,C1235,C1300,U0121,B2775,and C2318.

 

Did you ever check again with your code reader to see whether the INF code was 71, 72, 73, or 74 as shown in the manual excerpt S Keith posted, and then follow up with testing the conditions indicated in the table?

Chances are, if you look at the full manual, there will be at least a page on each of those possibilities with the test procedures you can follow.

-Chap

 

Do you have the manuals? Let me know if you need the appropriate pages.

 

About the best way there is of learning anything: pick a problem a bit above your knowledge level, obtain the right resources, work it through till you understand it.

-Chap

 

I had the same problem on my 2008 prius at 320,000 miles. Dealer told me it was most likely a brake stroke sensor and would be about a $500 job. I went home and reset the ABS computers by using a paperclip and jumping pin 4 and pin 13 on the diagnostic port. Once it reset all the lights went away and I got my power brakes back. I'm at 325,000 now and still going strong.