Dealership charging me $3800 + tax to replace a bad actuator on my 07. Is the repair worth it?

i would run from that dealer and get a second op.

as an alternative, just keep driving it.

if they mean the brake actuator, it may never fail.

 

For starters you're supposed to fix stuff when it's broken and they've failed to prove that it is broken... It's not like tires that wear out faster than the lifespan of a car that you replace before they've failed.

Secondly, Toyota stealerships will only replace parts with brand new, but it's a 14 year old car and you can get the exact same part used for 10% of the price they want to charge. And replacing with a used part the same age as the car is not like buying a brand new hybrid battery pack, which will likely will last longer than the car and you can put in your next Prius.

In other words, find a friend or family member or neighborhood mechanic who likes to work on cars and hire them to do the job once you get warning lights or the brakes start acting differently. If they say that they don't work on hybrid cars much tell them that it's easy if they just do some reading about it on PriusChat.

 

Where is the OP located? There are a few qualified 3rd party Prius repair facilities around the country.

JeffD

 

Do not use the dealer.
First do a brake fluid change for $130. This might be enough to eliminate any strange noises from the actuator.
If the actuator finally fails in 2 months or 2 years by turning the dashboard light on buy a remanufactured actuator $350 online and pay a competent local mechanic 3 hours of labor at about $450 total to replace it properly. The repair if needed would be $800 and not $4000.

 

@CarOwner I wouldn't be overly concerned at this point. If an imminent failure was likely, you would get a dash light before your brakes give out. They won't actually go out, but you will have no rear brakes, just front, and the pedal will be hard to push with no actuator assist. You wouldn't want to continue driving that way, but it won't be like no brakes at all. From all the reading I've done on Prius issues, it seems the brake actuator tends to fail in slow motion and you will be made aware of the problem, if it is actually a problem, when failure is imminent.

That's not to say it can't or won't fail, so it would be good to do some searching and reading about it so you have an action plan for if it fails. There are lots of good posts on Priuschat about user experience with failure, sourcing parts, and how to repair yourself if your comfortable doing the job. That way you'll be ready and know what to do if it does fail and more importantly with the advice you'll get how to tell yourself if the issue is serious and needs immediate attention. Probably the most important thing is learning how to listen to the actuator while driving because a failing actuator follows a common failure progression that you can hear before it goes really bad.

 

Others that have been working with the Prius longer than me could probably give a better answer, but I think you are right in that they are talking about the same device when they say actuator or accumulator. I'm sure others will chime in to give a better answer.

That video was correct in that it will take quite a bit of strength to push the brake pedal. I think he was wrong about the back brakes working, I'm pretty sure it's the fronts that continue working and not the back. In most cars the rear brakes are about 30% or your braking power and 70% for the fronts. So you will have brakes but you will have to press the pedal very hard and it will take longer to stop. The car is designed to at least have brakes if the actuator fails since the front brakes will still have hydraulic power for stopping, but without the actuator to help it's all leg muscle and no 30% brakes from the rears. If you've ever driven a car with power brakes that the booster failed you have an idea of what the braking will be like. You would want to get the car to a safe place (slowly and carefully) and not drive it until fixed. But it won't be like rolling down a mountain with no brakes at all.

A quick Google search show this;
How do you know if your brake actuator is bad?
The Most Common Symptoms of a Failing ABS Actuator Assembly

1. Increased effort to push the brake pedal.
2. ABS light coming on in the dash (usually in an amber color)
3. Brakes locking up frequently.

This was from Olathe Toyota, and sounds like reasonable symptoms of actuator failing.

The best early warning is hearing the actuator come on more frequently and for longer duration meaning the valves inside the actuator are leaking and the actuator is having a hard time maintaining pressure. The sound would be a bit more frequent at first and progressively worse over time. Also realize, the actuator is a noisy beast when working perfectly and for those new to Prius it's pretty hard to know if the duration or the frequency is too much or just normal. So just listen for changes in those two things and if it seems like it's coming on more frequently or for a longer period of time then it's time to be prepared for a change. But it will throw an ABS light if it goes bad, you won't have to wonder.

 

Get in your car, put your foot on the brake and press the power button to put the car in READY. Get a stopwatch (most smart phones have this feature in the clock/alarm app)

Let the car go through it's warmup cycle until the engine shuts off and the car becomes quiet. Keep radio off, etc. You may hear a slight hum, which would be the inverter cooling water pump running.

Press and release the brake pedal and repeat until you hear the brake actuator/accumulator/pump turn on to pressurize the brakes. This noise should be very obvious. Once you hear it start, take your foot off the brake pedal, and leave it off. After a few seconds, the pump will turn off. Start your timer. If your accumulator is bleeding down, pressure will lower and the pump will start again, even though you don't touch the brake pedal again. Measure how long it takes before the pump starts again. One of the 7 Gen2s in our family runs the pump for 3 seconds and is off for 6 seconds and has been doing it for several months. The car has never had the fault trigger and still drives/stops perfectly fine. The other 6 Gen 2s will have you die of boredom waiting for the pump to kick on.

I helped a fellow member with a battery issue several months ago and his pump was running practically continuous and the car would code several times a day.

Having techstream available makes the evaluation a bit more reliable since you can watch the actual voltage signal generated by the pressure transducer. It reads out in .01 volt increments and makes it easy to see pressure creeping down when bleeding off and raising back up when the pump turns on. 4 of our cars, the voltage never changes unless you press the brakes. 2 of them bleed down so slow it would take an hour for the pump to turn on and the black 2005 takes about 6 seconds.

 

Check if @Avi's Advanced Automotive is still operating his repair service. He was very active on PC in the past and seemed very knowledgeable. I haven't seen him on PC in in a while.

JeffD

 

The brake system is a pneumatic boost system. There is the brake accumulator pump which pressurizes the brake accumulator which is a pressure tank that holds the pressurized air. The pump normally runs only when needed. You hear it when you first step on the brake in the AM before turning on your Prius.

The Brake Actuator uses the accumulator pressure to assist the backup hydraulic brakes (AKA Power Brakes) to stop your Prius.

I would hope that the hydraulic Brakes would still function if the Brake Actuator actually failed. It would be like stopping a standard car without a working power brake system.

If your Dealer is being honest (questionable?), the actuator may be leaking pressure which would cause the pump to operate almost continuously - hence the buzzing.

JeffD

 

There is no pneumatic pump in the Prius brakes: it is a hydraulic pump that pumps brake fluid into an accumulator (essentially a pressure vessel).

Because liquids don't compress, there is some 'air' (straight nitrogen really) inside the accumulator, separated from the brake fluid by a bellows, so by design the nitrogen never leaves. The nitrogen is already under high pressure, and is further compressed when fluid is pumped in.

In principle, the actuator and accumulator are separate things, the accumulator being the supply of fluid under pressure, and the actuator containing the valves that direct it to the brakes. In practice, it depends on the Prius generation. In Gen 1 and Gen 3 the actuator and the accumulator are separate parts. But CarOwner has a Gen 2, where they were combined in just one part called the actuator. So in Gen 2 there's no need to figure out which one is busted.

As to what still functions when the brakes aren't fully functioning, that also depends on the Prius generation. Gen 1 and Gen 3 both have a similar design where the pressurized fluid 'boosts' your pressure on the master cylinder, so that even in case of some problems with the actuator or ECU, you have regular hydraulic braking, and it is even still power assisted until you have used up all the pressure in the accumulator; after that, it's without assist and you have to push the pedal really hard. Gen 3 works all four brakes in the fail-safe hydraulic mode, but Gen 1 only worked the two in front.

But again, CarOwner has a Gen 2, which was a detour into a quite different design, where accumulator pressure does not boost the master cylinder. It is a much more brake-by-wire system, where your pressure on the master cylinder is an input to the computer, which uses the actuator to send (higher) brake forces to the wheels. So it still feels like the same power assist, but it happens a different way. In Gen 2 it is more important to keep the brake electronics powered up to do that brake-by-wire thing, so there is a box of capacitors in back next to the 12 volt battery, just to supply emergency power to the brakes. Only Gen 2 had that. Once that power fails, you still do have purely hydraulic braking, but with no power assist at all, so you have to press really hard, and like Gen 1 it acts only on the front brakes.

 

Brake actuator $1134.95

https://parts.autonationtoyotagulffreeway.com/v-2007-toyota-prius--base--1-5l-l4-electric-gas/brakes--anti-lock-brakes

Possible to replace with a part from salvage yard?

 

People do that.

A new one will come with a large resistor that is matched to it. The resistor goes under the dash. If you get an actuator from a pick-n-pull yard. you might see if you can get the matched resistor from the same car. I'm not sure how critical it is really.