Constant beeping sound?

Stop driving the car. The presence of the BRAKE/ABS/VSC warning lights, the reduction in braking effectiveness, and the warning beep all convey the message that the car is unsafe to drive. Apparently you did not recognize the significance of that?

Have the car towed to your local Toyota dealer for assistance. Or if you want to DIY, get Mini VCI so that you can read the DTC logged by the skid control ECU.

 

welcome!

how many miles on her?

surprising that a new 12 volt battery didn't fix all the issues with your car, that's usually all it takes for prius repair.

 

You definitely want to check out those warning lights in your owners manual. It may be interesting reading for you. Glad to hear you're still able to park the car and turn it off, as opposed to being crashed on the side of the road.

 

Comical. The audible warning should be changed to “Danger Will Robinson, STOP Driving the Car!”

Hopefully you will have done as Patrick recommends: tow the car to a competent repair facility.

Read the owners manual. It is in your best interest. You will see and understand what the warning lights and sounds mean.

Stop ignoring warnings the vehicle has been telling you:
visual warning lights: ABS, VSC
audio: constant sound coming from the back
tactile: lack of normal brake pedal feeling

You ignored all 3 and are still alive (assumed). STOP pressing your luck, if you wish to live/remain uninjured.

 

Unmentioned heretofore in the thread is that you can get an abridged form of your brake trouble codes without any special code reader, by using a short piece of wire and counting some light blinks.

That might help you skip ahead to the part where you post the trouble codes here and get helpful responses, and not just people piling on you for ignoring the warning alarm.

-Chap

 

I just had this same issue happen to me today. The door open light + red caution light was on with a constant beep while in drive. It turned out to be the inside of the door was dented where it presses up against the driver door sensor. Now, my Prius has 280,000 miles on it, so that may be part of it. But I just put a couple layers of two way tape on the inside of the door where it presses up agains the sensor and voilà! Problem solved!

 

It wasn't the same issue. The thread was started by someone who had the brake system warning alarm going off.

But your tape on the door solution might work for somebody else who is hearing the door alarm. (The way the original post had the brake warning lights on, whereas you had the door open light on, would be one way to tell the difference.)

 

NO. OP in Post #1 reports

Your problem vs OP's problem VERY DIFFERENT. Your's does NOT involve brake failure.

 

In the last year, I’ve spent 8k on different repairs for my 2007 Prius. The 1st time at dealership they replaced the 4 hybrid batteries, last 2 times I took to the Toyota dealership and they charged me $165 to run codes said it was a sensor for the heat to not kick on when in hybrid not gas mode. Which heat has never stopped working. They ignore all the damn lights on my dash, reset them and give me a quote for something that doesn’t make sense to connect to the operating failure I experience. The whole time I’ve been saying it feels like the transmission not wanting to shift or the brakes. it’s been slooowww process of short alarms and driving different a little more each time. In between both trips to the dealership, I’ve taken it to our other mechanic shop, where they said all they found was 1-leak in the water system. Which they fixed, and I have the oil changed regularly, on time!
Today with my 3 boys in the car, the brakes stopped working. At 70 mph on us hwy 49. Literally I had to pump the brakes to slow down then pass my turn, to come to stop and call my husband. Who thankfully came got us and drove the car home the final 1/2 mile.
I’m exhausted with the run around and oddly enough there isn’t many mechanics around this massive town who work on hybrids,
Any suggestions?

Less than 150k miles

 

Hey did you find out what was wrong? I am having the same issue.

 

Pls post a new thread, and report your issue ... this is an old 5 years thread !

all constantly beep mean = STOP car ASAP. Pull off the road and tow to the nearest Toyota mechanic !!!!

I hope this is clear for everyone !

 

Bo, unfortunately, there is only one hybrid battery, located directly behind the rear passenger seat. There is also a 12v battery in the rear passenger corner of the trunk, that runs the 12v system in the car. Hopefully that's just a misunderstanding and the dealer didn't actually rip you off.

The non-stop beep noise is often (but not always) associated with the brake actuator failing to build sufficient pressure in the system. A proper diagnostic would be required for accurate troubleshooting. Did the dealer provide you with any printout of the codes? If you don't have one, you should be able to get it from them. You also could probably go to Toyota.com and resister your car VIN. That will enable you to look up all dealership records for your car, which should include any diagnostics performed.

Your brake system uses a small electric motor to run a pump. The pump pushes the brake fluid into an accumulator, which is essentially a pressurized holding tank. When you need to use the brakes, the pressurized fluid from this tank is used by the brake system. If the pump cannot build sufficient pressure when filling the tank, the loud buzzing noise kicks in to warn you. At that point, the brakes will operate more like manual brakes from a 1960's car and if you're not ready for it, it will be quite a surprise.

Where are you located? Maybe we have a member nearby that can help with a better diagnosis. If you happen to be near Columbia, SC, I'd be happy to throw my laptop on the car to get you better information.