My Brakes are Barking at Me

I pretty sure I have an answer to this brake "bark" problem. I took my Prius into the dealer today and they explained to me that the Prius does not use a braking system like a normal car, since braking is used to charge the battery. However, when the brake is pressed hard (while moving or at a complete stop) a normal braking system is engaged which makes the barking noise. This extra braking system is there for safety reasons in case the main braking system fails. My barking noise only happens when I’m at a complete stop and hold the brake down very hard, at which point I will hear the noise after a few seconds. If I hold the brake down lightly I do not hear the noise at all. This noise does not seem to be a symptom of a major problem, but merely an annoyance. I’ve decided to be easy on the brake and just live with it. I hope this helps.

 

I have this same problem (2007 Prius with 1200 miles) - I took it to the dealer who jokingly suggested I take it to the vet if it was "barking". They clearly didn't believe me, until low and behold, it barked for them!
We all had a good laugh, and then they found the problem. The Brake Actuator Assembly needs to be replaced. It's scheduled for replacement later this week.
In the mean time, we have lovingly named the car "FIDO"!

 

I own a 2006 Prius and mine started Barking about 3 months after I bought the car. Just as everyone else here, mine barks when my foot is on the brake. I can be stopped at a light or when I first start the car. I live in South Florida. The wheather is hot and humid. I've not been able to replicate the noise for the service department. My daughter heard it once when she was standing outside the car and I was inside. She said "Why did you honk at me?"

I'll be interested to hear if anyone has a true answer to this!

 

I went on vacation recently (California to Colorado to Nebraska and back) and have been back home for a week. My brakes were "barking" as soon as I got east of Wendover (Nevada/Utah) and stopped "barking" when I got back into Nevada on the return trip. I didn't have time to take it to a dealer while I was out there. I figured that since the same thing happened last time (see post #11 of this thread), I'd ignore it. This time I noticed that while I held the brake pedal down, I could hear several "barks" in a row.

I'm not too worried about it since things are back to normal, but I still wonder what it is (change in elevation/temperature/humidity all at the same time?). I've been up in the Sierras in cold temperatures and can't reproduce the noise. Hopefully I'll have time to pull into a dealership if the "barking" come back on my next trip.
- Ed

 

Oh, I almost forgot! I dug around and found a TSB on this issue. It's not a safety concern but if you gripe about the noise and show your dealer the TSB they will replace the brake system accumulator. I decided that I would wait for cold weather to return so I could show the deazler the noise (mine only does it in the cold) and then ask for the repair (if the language of the TSB had given me any safety concern I would have insisted that they do it immediately). Unfortunately I printed out this TSB last spring and now I can't find it and don't know where I got it. Anybody have access to those who can poke around for it?

Aha, I found the old thread with the TSB info in it.

http://priuschat.com/index.php?showtopic=5253&hl=

 

Ok, I asked about this over a year ago when my 05 Prius had this problem (and yes it is really annoying!) and I got the same guesses, "never heard of it" types of replies as well. I made numerous trips to the dealer with the dreaded "can't reproduce" response. Mine would only do it when cold and after sitting for several hours, and only when sitting still with my foot firmly on the brake. Finally in frustration (and near the end of the warranty) I went to the dealer and demanded to demonstrate the problem to the technician and he finally agreed with me the howl, screech, bark whatever you use to describe it was real. He checked with Toyota and their solution first was to bleed the brakes. This fixed it for a couple of days and it returned. I went back and they replaced the antilock brake accumulator. The problem has now gone away. If you have a Prius nearing the end of the 36,000 mile warranty have it fixed before it expires or at least get the problem on record because replacing the accumulator out of warranty is expensive.

So far, I haven't had the same issue on my 07 Camry Hybrid.

Good luck.

 

here is a description of my experience with the prius sea lions

first I live in boston, 10 ft above sea level for those of you who think its altitude related. I think this shows it is not.

Also I first started hearing this around 5K miles in probably october when the temp was in the 50s or 60s so i also dont think its terribly weather related. I have also heard it on 70 degree days

How I found the problem:
I didnt think it was a problem at first and then one time my gf was driving with me asked me who was honking at me. I said oh thats just my car, it seemed normal to me and i didnt worry about it but this got me thinking.

After this I started to notice it more. I noticed it came from the front left of the car. Sometimes in spurts of 3-5 "barks" like others have described. Then I noticed I could create the sound by pressing and depressing the break when not moving. It never happend while applying the brake while driving. The brake had to be pressed down as far as possible for it.

Then I was cruising priuschat and found this thread and the TSB so I decided to get it checked out

The Stealership (not at all in this case)
I went to a herb chambers dealership here in Boston and made my appointment on tuesday. The woman was somewhat skeptical telling me they've had lots of prii and that never made this noise and she was very adament about making me realize they'd have to test it first. I said I know it says that in the TSB and left it at that.

I made the appointment for thursday at 715. I showed up, worried I was not going to be able to produce the noise at the dealership. I decided to wait for the car and they said they'd check it out. I went and waited for 1.5 hrs in the waiting room when the guy came to get me and told me my car would be right up and that it had been fixed.

I dont know if they were able to produce the sound but they did drain the brake fluid for me AND they gave me a free car wash! I was thrilled that they believed me and fixed it and got a car wash it was great!

I've been drving for about 4 hours since then and have not heard it once.

 

Let us know if problem returns. Dealer just drained the brake fluid... and the brake actuator assembly wasn't, right?

 

its been a week now, the noise has not returned and yes all the dealer did was drain the fluid

 

I have a 2007 Prius with almost 50,000 miles on it. I have had this break barking noise issue with my Prius ever since the first service at 5,000 miles and have had break actuator replaced two times. The first time it was replaced the noise went away for about 3 months or so and then started coming back again. Now the noise is getting louder and happens to me all the time. While driving or standing, when i first turn the car on or after the car has been on for a while. I have had to finally contact Toyota directly because the local dealership has stopped responding to my requests to check breaks even after going for a test drive and hearing the noise several times. I am presently waiting for an outcome and hoping my breaks don't one day just decide to give out while i am on the freeway driving 85 MPH to work.

 

X2

But Mine does it below 60f.

 

This is my issue also! Barking brakes!

I see reference to a dead link regarding a TSB on this. Does anyone know which TSB concerns this brake actuator problem?

Edit - I found the TSB. It's in this thread:

http://priuschat.com/forums/toyota-.../29211-tsb-br001-07-brake-actuator-noise.html

 

Automotive Recall and Technical Service Bulletin Titles for 2004 Toyota Prius L4-1.5L (1NZ-FXE) (Hybrid). ​

TSB Number & Issue Date TSB Title
SSC40D MAY 04 Recall - Hybrid Vehicle ECU Reprogramming ​

TSB Number & Issue Date TSB Title
LSC40J NOV 04 Campaign - Navigation Software Upgrade ​

TSB Number & Issue Date TSB Title
SB0122-08 JUN 08 Keyless Entry - Smart Key(R) Battery Diagnostics
SB0088-08 JUN 08 Engine Controls - MIL ON/DTC P0125 Stored in Memory
SB0087-08 JUN 08 Cooling - Noise From Coolant Heat Storage Water Pump
SB0048-08 JUN 08 A/C - Compressor Oil Service Procedures
SB0038-08 APR 08 Engine - Cylinder Head Cover Baffle Precautions
SB0030-08R APR 08 Lighting - HID Headlamp Diagnostic Tips Update
SB0020-08 MAR 08 ABS/TCS - Zero Point Calibration Information
EG001-08 JAN 08 A/C, Cooling System - MIL ON/DTC P1121 Stored
PG007-07 NOV 07 Vehicle - Replacement VIN Plate Information
EL015R-06 NOV 07 Keyless Entry - Smart Key(R) Specification Information
EL010R-07 NOV 07 Keyless Entry - Remote Transmitter Programming Guide
BO017-07 OCT 07 Restraints - Seat Belt Tongue Plate Stopper Service
SS006-07 AUG 07 Battery - Absorbed Glass Mat Battery (AGM) Information
EG047R-04 AUG 07 Engine Controls - MIL/Master Lamp ON/DTC P3191/P3190
SS004-07 AUG 07 Restraints - SRS Component Disposal
EG001R-07 JUL 07 Cooling System - MIL ON/DTC P0A93/Info Code 346
EG045R-06 JUL 07 A/T - MIL ON/DTC's P0AA6 OR P3009/Info Codes 526 & 613
PG003-07 JUL 07 Hybrid Systems - Emergency Response Training CD
TC010-07 JUN 07 A/T - 'World Standard' Transmission Fluid Information
EG034-07 JUN 07 Engine Controls - Bank 1/Bank 2 O2 Sensor identification
BR002-07 JUN 07 Brakes - Parking Brake Lamp ON After Releasing Brake
EG058R-06 MAY 07 Hybrid Controls - MIL ON/Multiple Hybrid Codes Set
EG025R-05 MAY 07 Hybrid System - MIL ON/Multiple DTC's Set
SS002-07 APR 07 Engine Controls - ECU Flash Reprogramming Procedure
EG050R-04 APR 07 Engine - Oil Specifications
ST005R-01 MAR 07 Steering/Suspension - Vehicle Pull Manual Supplement
TC003-07 MAR 07 Drivetrain - Driveshaft Replacement Precautions
BR001-07 FEB 07 Brakes - Squeak Noise When Pressing/Releasing Pedal
AU001R-06 FEB 07 Audio System - Quick Reference Diagnostic Guide
EL003-07 FEB 07 Air Bag Systems - Repair Manual Supplement
BR012-06 DEC 06 Brakes - MIL On/DTCs C1341-C1344 After Pad Replacement
EL013R-06 DEC 06 Cell. Phone - Bluetooth(R) Compatibility
PG001R-06 NOV 06 Electrical - Battery Maintenance and Testing
EG024R-05 NOV 06 Hybrid Cooling System - DTC P1121 Set/MIL ON
EL010R-04 NOV 06 Instruments - Fuel Gauge is Inaccurate
CRIB146 SEP 06 Body - Paintless Dent Repair Information
PG002-06 JUL 06 Hybrid System - Inverter Removal/Installation Precaution
PG011R-05 JUN 06 Fuel System - Fuel Injector Cleaning Procedure
EG017R-05 JUN 06 Hybrid System - MIL ON/DTC's P0AA6 or P3009 Set
NV004-06 MAY 06 Interior - Front Seat Squeak Noise
EL004-06 APR 06 Lighting - Automatic Headlamp Leveleing Lamp Flashing
BO017R-03 APR 06 Body - Interior Trim Panels/Garnish Loose
PG007R-03 MAR 06 Hybrid System - HV & Auxiliary Battery Maintenance
AU001R-05 FEB 06 Audio System - Amplifier Won't Turn OFF/Battery Drain
EG063-05 DEC 05 Ignition System - MIL ON/Misfire DTC's Set
BO022R-04 DEC 05 Restraints - Seat Belt Extender Availability/Application
SS003-05 NOV 05 Audio System - CD Player Skip Verification
BO014-05 NOV 05 SRS/Interior - Seat Cover Replacement Caution
PG008R-03 NOV 05 Antitheft - Smart Key System Function Clarification
EL008R-04 NOV 05 Antitheft System - Smart Key(R) Registration Supplement
PA002R-02 OCT 05 Paint - Paint Stains Under Rapgard
SS003R-02 AUG 05 Antitheft - Diagnostic Tester Immobilizer Function
EG029-05 JUL 05 Engine Controls - False MIL ON/P0A7A/IC 325
EG045R-04 JUN 05 Engine Controls - Entering VIN When Replacing PCM/ECM
EG022-05 MAY 05 Engine Controls - MIL ON/DTC P1151 Set
EG019-05 MAY 05 HV Service Plug - No 'Ready ON'/MIL ON/DTC's Set
EG014-05 MAR 05 Cooling System - Radiator Cap Inspection Procedure
SS001-05 MAR 05 Computers/Controls - CAN Interface Module Initialization
PA003R-02 FEB 05 Paint - Refinishing Bumper Cover
EL002-05 JAN 05 Instruments - Multi-Display Functions are Inoperative
TC002R-03 DEC 04 Engine/Transmission Controls - Resetting ECM Memory
AC009-04 DEC 04 A/C - Sensor Inspection Procedures
PA005R-04 DEC 04 Paint - Iron Rust Contamination Repair
TC006R-03 DEC 04 A/T - New Fluid Introduction/Compatibility
CRIB141 OCT 04 Paint - Chip Resistant Coatings
EG038-04 SEP 04 Engine Controls - MIL ON/DTC's P0136/P0138
BO017-04 AUG 04 Body - Rear Door Frame Black-Out Tape Wrinkled
EL009-04 AUG 04 Electrical - Power Window/Roof Initialization Procedure
EG023R-04 JUL 04 HV Battery - MIL ON/Multiple DTC's Set
PG002-04 APR 04 Vehicle Information - Emergency Response Guide
EG018R-03 MAR 04 Engine Controls - MIL ON/DTC's P0136/P0138 Stored
EL001-04 JAN 04 'Smart Key' (R) System - Poor Performance
TC006R-03 DEC 03 A/T - Type WS Fluid Service Precautions/Identification
SS002R-01 SEP 03 Engine Controls - ECU Reprogramming Procedure
CRIB135 SEP 03 Paint - Paint Codes
PA006-03 JUL 03 Paint - Paint Colors - All
CRIB127 MAY 03 Glass - Windshield and Fixed Glass Bonding
PA002-04 APR 03 Paint - Color, Scratch Resistant & Anti-Acid Paint
CRIB122 FEB 03 Body - Body Sectioning ​

 

We have 3 Priuses of various miles up to 20k. All three "bark". I would call it more of a woff....woff, than a bark. I don't think it is brake related, but we do only hear it when we are going slow. Funny thing is whenever we really listen and try to figure out where it is coming from it stops, but we will keep on trying. It sounds like a dog is saying woff......woff about a block away. Sometimes it is just a single woff. Sometimes there are several within a minute or so and sometimes you don't hear it for a long time. Is this the barking you guys are talking about? My car makes all kinds of funny noises, but they all sound designed in, except the woffing.

 

Hmmm...

Lately when sitting in traffic at a stop light, we've occasionally heard what
sounded like someone honking. We thought it was an impatient driver trying
the "Get out of My way! I am the only reason why the universe exists, I am
outraged that My Primacy is not evident!" gambit.

But now, we've heard the honk in the driveway on start up a few times, and
there wasn't a moving car anywhere in sight. What the heck?

Well, now I know, it's my brake system. But I don't think the Toyota techs
are going to do the TSB's fluid/actuator job unless I can demonstrate the
sound to them.

I need to find a way that I can induce the sound on demand.
Has anyone found a reliable, repeatable way to do this?

 

Mine does it consistently if you put your foot firmly on the brake pedal while at a stop in Park- like when I'm getting ready to shift out of Park into D or R. If I stay in Park and continue to slowly step firmly on the brake pedal, and release again, it will bark bark bark bark quite a bit. The colder the weather, the more it does it.

I actually took my 07 in for this issue on Tuesday morning (when I knew it was going to be extra cold). They didn't hesitate to do the actuator replacement- another dealer already did the bleed procedure last year, and that didn't fix it. The TSB says that if the bleed doesn't fix it, that you replace the actuator. But they had trouble getting the part and eventually figured out that the actuator is on national backorder (that's what my dealer is telling me, anyway). While we wait for the parts to come in, I am driving the car without worry. The TSB says that it's just a noise, not a safety issue. If it were a dealer telling me that, I'd be skeptical, but given Toyota's deep pockets, it would be very expensive for them to be wrong about that one.

 

OK, my service adviser just called to tell me that the part came in. So apparently the actuator is backordered, but they're only a couple weeks behind. Not too bad.

 

OK, the work is done, and the noise is banished. But wow, you should have seen the warranty charges they sent to Toyota... $2250. The part alone is $1769!

 

There is a TSB on this problem from Toyota. I have heard the noise described in many ways, including barking. Sometimes it sounds like more of a squeak than anything else. It also will mainly occur when you are sitting still and pressing on the brakes.

The fix is to first bleed the brake system. This has to be done with the factory techstream scantool. I have fixed about 5 of these cars now by just bleeding the brake system. I found small amounts of air in the brake systems of the cars that were making the nosie. If bleeding the brakes system does not fix it, then the ABS actuator will need to be replaced. So far, I have not had to replace an actuator. This noise is not a safety issue, just an annoyance.