I bought a Honda CR-V iBooster Gen 1 - Now what?

[Gregski]

one of the things that goes away with an EV conversion is vacuum, and that really sucks when it comes to brakes, or wait, it doesn't and that's the problem, there are a couple ways to solve this problem, among them is ditching your current tried and true and reliable system for something more exciting and shall we say modern - aka the iBooster

if you have done any research on the topic of anything iBooster than chances are you discovered the wonderful resource that is EVCreate and are familiar with Lars' work and write up, by no means am I trying to replace that or say that this is more better, this is actually all based on his work and I am just someone who is going to plagiarize, sorry, follow his instructions and add pictures, videos, and most definitely bad humor to the process

the iBooster is a black box that uses electricity rather than vacuum to keep your calf muscle from over developing and can be found in half a dozen different vehicles, you can get it from a Te$la and pay more or get the exact same thingie from a Honda and pay less, it also comes in two generations this write up will focus on Gen 1 and I will do a separate one for Gen 2

TABLE OF CONTENTS
Lars Rengersen's write up on all things iBooster over at EVcreate.nl iBooster donor vehicles iBooster CAN-BUS research Wiring the Tesla iBooster Installing the iBooster Electric power brakes Good Enuff Garage BOSCH iBooster YouTube Playlist OpenInverter Wiki Brakes, Electrically Boosted:

[Gregski]

So how much do these things cost, and where can we get them?

this much, and on eBay

[Gregski]

these come as appendages on the Honda CR-V (fifth generation) 2017 - present

[Gregski]

highly recommend trying to score one with the wire harness pig tails, there are a total of three, one big main one for the brain module, one medium sized one for the pedal sensor, and yes a third little one (optional) for the fluid container level reading thingie (mine did not come with one in the pic below)

[MattsAwesomeStuff]

*rubs hands together*

Guess what showed up in the mail today?









Couple things I notice...

1 - Compared to the one on the EVcreate post, your and mine have tiny fluid reservoirs:



However, EVcreate seems to know this, and apparently there's a main tank neither of us have, that's connected to this baby tank with a hose? I wish I'd gotten a normal tank than this hokey double-tank, but, oh well, I didn't even pay for the master cylinder or the tank.



2 - I think our black box is on the wrong opposite side (or the whole thing is rotated upsidedown at construction). Unless my mind's playing tricks, I can't orient mine to match the EVcreate one, stuffs just in different places. Mine came off a 2018 CRV.

For Americans, here's an interchange search (bit stubborn, you can sort by price descending, but can't flip it to ascending, so you have to go to the last page). Make sure after you're done, in the upper right, you select "all interchange parts", so it'll find compatable years, not let you be overly prescriptive with that exact year if the parts are the same:

https://car-part.com/cgi-bin/search.cgi ... serPage=13

I paid $55 USD for mine plus shipping (none within 500 miles of me, in Canada, but lots out east), which was a fairly common low price. I asked for the wire stubs and said I wouldn't be opposed if the master cylinder came with it, but I didn't want to pay extra for it. I was told wire stubs was probably fine, but no, master cylinder is sold separately.

And then what I got was... no wire stubs, but a free master cylinder (they probably never sell them and it's extra time and cost to remove it).

So, I guess I have to shop for connectors now, damnit. EVCreate sells a kit, but it's 99 euro: https://www.evcreate.nl/shop/brakes-whe ... ector-kit/ ... I paid $55 USD for the whole booster.

It's a Bosch unit, as expected.



...

So, a few things:

- I'm not sure if I'm going to use this master cylinder, or take the original off of my vehicle and then mechanically adapt it to this booster. I don't know enough about what goes on in there to know how different they might be. I know the end result of a brake booster is just a plunger that pushes on the master cylinder, so, mechanically that's not challenging.

- This appears to only have 2 ports. I think my car's original master cylinder has 4 ports. So, if I do use it I'd have to create some kind of splitter or manifold, and now I'm wondering to what degree this was engineered into my original master cylinder so that one failed brake line doesn't lose all braking power to that half of the car.

Anyway, your timing is impeccably useful to me, carry on documenting

[Gregski]

ha ha, awesome stuff Matt

1 - Compared to the one on the EVcreate post, your and mine have tiny fluid reservoirs:

indeed, and I was entertaining replacing the Honda CRV master cylinder / reservoir combo with one from another rig but since these cars are so new we would have to buy these new from the Stealerships, so I found this Honda CRV remote reservoir on eBay and since I don't like money, I made an offer and $60 bucks later it was at my doorstep

ahem, speak for yourself mister, held on with only the finest zip tie, temporarily

[Gregski]

OK, my OCD is off the charts but I am posting these 2020 Chevy Bolt iBooster pics on here (Honda subforum) so you can see that it has a bigger fluid container on it

you're welcome

[Gregski]

Nobody: Hey do you happen to have the part number for that master cylinder?

Me: 01462-TLA-A00



Nobody: Any idea what it costs brand new at the local stealership?

Me: $406 [ahem] plus tax

[Gregski]

here I found it at HondaFactoryParts.com for a hundred and forty bones less

[MattsAwesomeStuff]

here I found it at HondaFactoryParts.com for a hundred and forty bones less

$50, including the master cylinder.

And that's not the cheapest.

https://www.car-part.com/cgi-bin/search ... Search=int

Just the reservoir would probably be pretty damned cheap if you had a yard that had one nearby.

[Gregski]

thanks Matt, your timing or is it my timing is impeccable as I literally dropped $80 bucks on a replacement Honda CR-V master cylinder just this morning, since we suspect my original one is faulty (the pedal starts out firm then slowly drops down to the floor with no electricity supplied)

these Honda CRV ones seem hard to find, my local wrecker in Rancho Cordova of all places (huge collection of wrecking yards, perhaps the biggest in these Independent States of America) didn't even have one, said $75 bucks if they did

[MattsAwesomeStuff]

Just because it's always better to see a damned diagram than a text list of descriptions, here's a screengrab from SuperFastMatt's brake booster vid showing how to wire things on the Gen1:



Note that if you didn't get ripped off and they actually gave you the wiring stubs, the default wiring harness already connects the 4 wires between the sensor and the ECU (these might as well have been run internally). Leaving you with only the beefy positive, negative, 12v control, and 12v ignition switched.

It would be great to know if these connectors are salvageable from any other vehicle, since these are still too new to be appearing in junkyards.


Source:



And, for bonus context since many of us are going to have to do this too, here's same guy talking about doing brake lines:

[Gregski]

Thank you Matt you are doink God's werk! Mine came with the two pig tails, but when I bought a Gen 2 the local junk yard would not cut them off the main wiring harness, first they wanted like $300 bucks for what they called the dash harness (not the engine harness) saying they sell these harnesses / harn eye to flooded cars in Florida, then as my nagging increased they said they sell them for like $200 bucks, and finally the guy said look I may cut you off some ends for like a $100 bucks (but I passed on the deal)

26 way BOSCH Connector housing Part # 1928405762

bosch-logo-res-340x111.png (6.54 KiB) Viewed 20772 times

[Gregski]

Fun Fact: the Bosch big plug with the lever on it is indeed interchangeable with the Gen 2 iBooster from it's Honda Accord brother (thread coming soon) however the smaller doodad is not

[Gregski]

what the inside of a 2018 bad Honda CR-V master cylinder looks like

[mjc506]

It's amazing these things work as well as they do with all the gunge in there. Fixable with a clean and new seal kit?

[Gregski]

It's amazing these things work as well as they do with all the gunge in there. Fixable with a clean and new seal kit?

I am not sure there is a kit, I will call my local stealership and find out, check out this video of how bad it looked

[mjc506]

mmmmm grungy

[Gregski]

It's amazing these things work as well as they do with all the gunge in there. Fixable with a clean and new seal kit?

so just got off the phone with our local dealership which actually was a family owned business where my mom and dad bought a Honda Cervix back in 1986 and it was a decent place to go for 30 years, then they got eaten by a bigger fish (some investment group and you know the rest)

anyway after 15 minutes of attempting to order a part without a VIN the gal there said Honda does not make rebuild kits and for me to try NAPA, well the funny thing is I went to NAPA first and they did not even sell the part cause it's too new, and oh by the way a brand new master cylinder will set you back $450 and it's on back order

[MattsAwesomeStuff]

Okay guys, at this point this is less of a rescue and more of a recovery

No, that sir, is an autopsy.

All I can think of is that the hose came loose or the lid was left off and actual dirt got into it.

This came from a junkyard, so, I wonder, did this vehicle happen to get into a crash because.... it's brakes failed?

I'd say whatever it is, that's bad luck, not a bad design. There's no way that's normal.

We all know brake fluid is hydrophilic and does need to be replaced every few years, but, goddamn.

[Gregski]

No, that sir, is an autopsy.

All I can think of is that the hose came loose or the lid was left off and actual dirt got into it.

This came from a junkyard, so, I wonder, did this vehicle happen to get into a crash because.... it's brakes failed?

I'd say whatever it is, that's bad luck, not a bad design. There's no way that's normal.

We all know brake fluid is hydrophilic and does need to be replaced every few years, but, goddamn.

autopsy, lol, luv it, so here's just another close up of that old master cylinder

[Gregski]

SOME SPECS

the 2018(ish) Honda CRV master brake cylinder piston is 1" in diameter (aka bore) and travels 1.5" (aka stroke) in and out of the tube thingie

[Gregski]

nice professional video on the BOSCH iBooster

[Gregski]

so after eyeballing the old Honda CRV master cylinder some more I learned it actually houses not one but two pistons in series formation one behind the other


here is the front piston, it appears to be hollow

and here's the second one lurking behind it

and here are both pistons in serial formation

[Gregski]

so let's talk fittings, for some of you this may be straight forward but for those needing to adapt to US "Standard" standards it make require more maths

if you're lucky, your used CR-V master cylinder may come with the fittings still inside of it, and if you are supper lucky they lines may have been cut just far enough from the fittings to get a hack saw blade in there and gently cut off the jacked up ends in order to get the old tubes out (less fortunate see my Gen 2 thread, ha ha)

these beauties are stock OEM M12-1.0 fittings (not bubble, we will get to bubble later on)

I have not confirmed this but I believe these run the 6mm brake line (1/4" in American)

the easiest brake line you will ever work with, you're welcome