Patrick asked me to document this change. While going to post this, I found this thread: http://priuschat.com/forums/gen-ii-...7-brake-actuator-replacement-in-pictures.html which already documents the change. However, since I already spent the time to make a document, here is my version. Note, I have yet to bleed the brakes. The car is working fine though. I will bleed the brakes using the Autoenginuity tool, but since the car seems OK, I will do it later, to many other pressing things right now. I have not found clear directions for bleeding the brakes with this tool yet, so it should be interesting. Furthermore, since they seem to work OK now, how would I confirm it is done correctly?
LOL I did seal the connector better, but I will see how it behaves over time. It did give me trouble in the past, but never blew the fuses, so it really got drenched. Two weeks later, and the connector was still wet inside. We will see.
.. tasked to report about actuator and sensor characteristics and one of the characteristics is saturation...
So what are symptoms of a bad actuator? I assume you got some warning light or code. Also, that part looks expensive...
wouldnt this car have been more reliable without all the fancy pancy break fluid pump and brake by wire ? or is that all necessary for ABS to function ....
There's hardly anything in that braking system that you wouldn't find in plenty of other modern cars, non-hybrids included, as can be seen in the Brakes section of this general automotive technology book, for example. (Look around pages 1559 to 1564 or so.) Being a hybrid offers one additional reason to choose a hydraulic booster in place of the engine-vacuum-powered booster in grandpa's car, given that a lot of the time you have a stopped engine and no vacuum. But then so many of the modern safety advances like ABS, stability, traction, pre-collision, pedestrian avoidance, etc., all rely on having pressurized fluid on tap at all times already. That's just kind of baseline functionality these days. Regen in a hybrid is really no change to the braking hardware at all, just adds a software negotiation between the braking and the powertrain ECUs over how much slowing each one will take responsibility for. It may be true that some of the added complexity doesn't strictly make the car less likely to need repairs. But generally it's there to support features that are added to the car to make you less likely to need repairs.
this has a part number of 44510 -- however there is a dash afterwards .... the toyota tundra has the same part number 44510 but the - 0c070 ... I wonder if it is the same thing ..... I just saw a a part number listing for prius and it comes to the same 1st part 44510 but ... the 2nd part is 47050.
acquired replacment accumulator ABS assortment (block of aluminum, valves and pumps) .. a used item , clean (seemingling) with part#44510-47051 (maybe this is off an 06) - guy claims i have 30 day warranty... claims to send me procedural list .. claims some computer programming is needed after replacment ABS system installed (I wonder why i didnt hear any of this from things i've been reviewing -- maybe he meant using computer to AIR bleed .. his english was not great) -- removed wiprs and under-cowl - inv cover and most connectors then can place INV to side (leaving coolant connected) will pick up on this in AM - only lost 1 INV mount bolt so far (hopfully to be found 2morrow) - I put most bolts back in holes they came from so I dont have to worry about where things go and where they came from ...(and they are less likely to get kicked over in a can and spill) -- somepeople use the ziplock method .. sharpie and ziplocks for the fasteners ... --- rather concerning that the yard pull replacement unit was fresh inked at pickup time with X X on the 2 cylindrical shaped units ... when asked the response was 'that is means u have warranty ' (i always thought u put on x on something when it is bad or wrong .... ) BTW - i weighed it and the assembly comes out to around 14 pounds !!!
iSTARTED ohming out the replacement actuator and found that everything seemed good except BM2 - BM1 ... I also did see the 500 ohms for BM2-MTT and BM1-MTT ... test 3 and 4 on the list is supposed to give less than an ohm (my hf meter only goes to 1.5 (lowest) direct connection so .. when I saw 3 ohms for test 3 this is about twice what i was supposed to see .. --hopefully this is not too much of an issue..
It is important if you are ohming this connector to know that there is 2 rows above the seperator of the fine pins ... of those 2 rows there are 2 rows of 10 pins .. there are missing 'blanks' on each side of the 10 pins .. 2 to the left and 2 to the right ... So it's very confusing reading this file page 8 of 17 ... the table of tests on the connector of the actuator. in big letters the pg title is 'the table is incorrect for the 1st 2 measurements - ' (referring to 2 different pins for the 2 measurements) ... whilh should give between14.6 and 24.6 ohms .... I 'm getting an open condition on my readings between 6 and 20 (2nd pins over from right (as there are 2 pins not there that are counted ) ... I don't know where this file picture of the measurements for the 33 pin connector come from but I didnt find it in the BC- portion of the prius technical manual .... (the 240 page section ' BC ')
The 'programming' the seller was referring to is most likely performing the zero-ing of the linear valve offset or whatever it's called. That's going to require a scantool or techstream.
yes -- and so far .. have not gotten much response from him -- except' i have to look into it' .. -- yeah because i was smart enough to ask this CL ad for a 'paper warranty' (not) ,,,, -- well there was alot of circumstances around the meeting place / distractions ... not like walking into a shop with a front desk ...
what a major pain in the A*& !!! removing the damn thing is .. all the lines and harnesses surrounding it shoved way back .. its bad enuf the thing weights 14## .. but then they have an additional dampening weight underneath of 5#??? connected to the bottom of it .... so its about 20# to navigate and negotiate out of there ... one or 2 nuts (just when u think your ready to pull out ) .. last things holding a few lines to the assembly and they have other hoses positioned in such a way that the line of torque to a socket is impeded .. it is a royal nightmare removing a couple of nuts holding down hose brackets ....
I have 5 actuators in the garage that I've removed from salvage yard cars. I'll be installing two of them in the next month or two. Been reading up a lot on it also. Seems like the plan is to use a helper. One person supports the actuator and the second is the interference mover while sliding it out and then back in. I'm sure it'll be challenging. Salvage yard ones are so much easier since you don't have to worry about putting it back together. I did read that using a 2x4 or something similar to wedge the brake pedal down works well to keep the brake fluid reservoir from draining. Any truth to that?
For sure on a helper i was thining allabout one as i was fretting and bending my back over to reeeeeaach into the hood .. and farting with that tdamned nut on the side that is blocked by the hoses ... challenging means alot of time and patience .. hope the helper gets paid so he has the same 'time and patience' !! a\i have used some fence wood to kind of stabilze the invertor 'hanging ' sitting on the front of car as all coolant hoses have remained intact .. i didnt wedge any brake pedal down yet .. i did take a turkey baster and move the resoirvor down from max to min and did drain the hose leading to supply the assembly into a small bottle (prob half of that still went on the ground) the excitement ? of installation remains .. i am hesitant because my yard pull part that sort of questionable non-english character sold me is not ohming out according to the 33 pin tests in the pdf supplied with this thread .. 'procedural file' archive .. i almost wasnt going to take it out but it needed it anyway .. i was hopeing between then and now someone may have chimed in about the ohm tests listed on the pdf file ... i did watch several utubes .. and did see a guy wedge a stick under the seat to the pedal for a 1 man bleeding procedure .. i think if u have techstream u may be able to get away with a 1 man bleed also ... 0
Did you measure and subtract the resistance of your test leads themselves? For measurements down in the ohm-or-less range it matters....
