2010 Prius: Intermittent Dash Lights & No Regen Braking

Where does the vehicle park and reside like state I don't need your street address It seems a lot of people here having problems with rats cats and general livestock living in their vehicles. A quick way to check this is to drop the glove box clips pushing in on the sides and letting the glove box just aim to the floor and pulling out the cabin air filter tray looking for the mouse droppings and the chewed up filtering material Do you have this???

 

Did any of the threads you looked at mention how to get the brake trouble codes when the scan tool you're using won't show 'em?

Here you go: Blink (a/k/a Flash) Codes – How to. | PriusChat

 

Anything permanently plugged into OBD port?

Gotta ask: have you cleaned the EGR components and intake manifold?

 

Those details are in the manual and I have trouble keeping them straight in my head. I think some ECUs keep both current and 'historical', or 'permanent', (or both!) codes, which a scan tool can show you, but I think some of them only blink out the current ones, when you use the blink method.

I remember noticing one of them (the airbag ECU, maybe) would blink out either the current or the historical codes, based on whether you placed the jumper wire before or after turning the car on. But I don't remember seeing anything like that mentioned for the brakes.

 

Well, keep breathing, right? From the explanations on this page:

Blink (a/k/a Flash) Codes – How to. | PriusChat

The 43 and 45 on the traction light just mean "hey, look at the ones on the ABS light" and "hey, look at the ones on the ECB light."

The 42 on the ABS light just means "don't miss the ones on the ECB light".

The 36 on the ECB light just means "don't miss the ones on the ABS light".

So you've got ABS 33 and 38, and ECB 62 to think about.

C0210/33 and C1238/38 are both about the wheel speed sensor on the right rear, or the wiring to it. That could be quite simple.

C1214/62 could be a little more work to pin down. The brake-by-wire system is trying to shoot for and hold a certain fluid pressure while you're braking, but isn't able to hold steady at the right pressure. That can be something as simple as a wobbly brake rotor, or it can be something else like leaks somewhere or a bum actuator.

Any chance your right rear wheel hub has gone wobbly?

The tire codes C2123 and C2124 just mean that two of your in-tire pressure transmitters have stopped transmitting. If they are the originals, their batteries might have pooped out.

C2175 means the tire monitor isn't getting a good vehicle speed signal. That signal is generated by the brake ECU, based on the wheel speed sensors, which the ABS light has already complained about.

 

Both our rear speed sensor wire harnesses are plugged in by friction only, after rear solid axle replacement. The connector lock mechanism is a royal pain, prone to break.

Confirmation that wires are plugged in is relatively easy, even without raising the car, if you just squirm under a bit.

 

Also, the speed sensor is built into the hub, and if the hub has gone old and wobbly, that might be behind the C1214 as well.

 

Im having a similar issue since changing my front brake pads. I reset using the OBD short method, but it kept happening, so I flushed the brake fluid, hoping that would help…I thought it worked until I got all the dash brake warning lights again today…wondering if it has to do with the brake pump? Only began after changing brake pads though…

 

As already covered on this page, linked in #3 above:

Blink (a/k/a Flash) Codes – How to. | PriusChat

So next time you have that OBD short jumper in your hand, use it for what it's for, and tell us what the trouble codes are.

 

“For some reason, ludicrous numbers of people on PriusChat have only ever heard of this method as a way to blindly clear codes”

I came here for information, not snarky remarks. I am not a trained Toyota Technician, just someone looking for a resolution to a problem with my car. You seem frustrated, probably because people keep making the same mistakes from your perspective, not our fault, we’re just trying to find solutions to problems, probably what brought you here originally. Doesn’t give you permission to put others down. Having said that, I appreciate the link.

 

And so when you come to PriusChat, you need to be able to find that information (including how the code blink feature works and what it's for, and what are and aren't effective ways to use it, which turns out to be some of the information most often needed around here).

The problem isn't that the information isn't covered here where people can find it; after all, it is in that PriusChat wiki page, and also has been repeated in countless individual threads , so a person who comes here and looks will stand a pretty good chance of finding it.

The problem is more that people come to PriusChat after having googled and found some botched advice somewhere else, that only talked about the code blink feature as some kind of "reset trick", and then they'll post about that here. Because PriusChat threads stick around and other people later find them, those posts need to be followed up with redirection to the right information, otherwise they become part of the problem when later people search and land on them.

I understand perceptions can differ, but on rereading what you quoted (which was, itself, quoted from the existing wiki page), I still see nothing that put anybody down.

Pointing out something unfortunate that happens to ludicrous numbers of people isn't saying anything disparaging about those people. They have simply had something unfortunate happen to them. Everybody benefits when that happens less.

 

I made two vids, one is the actual noise coming from the pump, the second is the flashing dash codes

I’m assuming there’s an internal leak and/or the accumulator needs to be replaced, I’ve read that the booster/accumulator & master cylinder both need to be replaced as there’s no way to diagnose where the leak is…any input or advice would be greatly appreciated

 

The video clip is a bit short to be sure all the codes are shown.

ABS is shown blinking [something that ends in 2], then a definite 42, then something that's a 4 and at least 2 when the clip ends. So maybe we'll say it's just blinking 42.

The VSC light isn't in the clip because it's over to the left of the speedometer in this model.

The ECB light is shown finishing up a code that ends with 9 at the start of the clip, and starting one that starts with 6 but the second place only gets to 7 when the clip ends. So maybe the only code being shown is 69, but I can't be sure.

As the blink codes how-to page explains, the 42 on the ABS light only means to pay attention to the code(s) on the ECB light.

ECB blink code 69 is C1391, a problem maintaining fluid pressure in the accumulator. It can be caused by problems in either of these assemblies:



As you see, the booster and master cylinder are combined in the upper assembly, and the booster pump (so be careful not to confuse 'booster' and 'booster pump') is combined with the accumulator in the lower one.

While the leak can be in either assembly, if you're willing to play the odds, the upper assembly contains a lot more things to leak.

Sometimes, if the leaking is pronounced enough, a mechanics' stethoscope, touched to both assemblies, can help pin it down.

The tire pressure light appears to be blinking 21 (C2121, loss of signal from transmitter ID1) and 75 (C2175, issue with either the vehicle speed signal from the brake ECU or the RSSI signal from the TPMS antenna/receiver).