Toyota Aqua ABS issue explained and how to manage it

[blueazure]

Aqua user here . i have 2014 model L package, self import from japan -

my vehicle has done 230,000 KM + on the ODO and going great. fuel average is still excellent and i face no issues

i have recently experienced ABS issue in my car and got it fixed. in this write up, ill explain this common issue and how to manage it . Usually, people panic once the dreaded ABS check light comes and they hurriedly sell their car. !

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. what is the ABS system in AQUA?

all JDM vehicles have standard ABS . as we all know, its a safety feature and prevents wheel lock up on hard braking.

now on the AQUA( and prius) , the ABS system is actually a dual motor assy with electronic controller. the system is more than an ABS system and it does the following functions:-

A ) the ABS pump operates the anti lock algorithm for the brakes
B) the ABS pump operates the stability control algorithm for the Traction control system - this system helps with grip under adverse conditions
C) the second motor on the ABS pump harnesses energy from the regenerative system while braking and charges the HV battery ( the charging bars on instrument cluster you see going down while braking is actually the ABS motor working as a dynamo and charging battery)
D) the ABS pumps helps with assistive braking and applies appropriate pressure to brake booster to ensure smooth braking feel which is characteristic of these hybrid vehicles
E) the ABS pump operates the brakes to kill speed when we RESET the cruise control switch ( down )

why does the ABS system fail ?

as we can see, the ABS motor is a critical safety system and works constantly while driving
naturally, this being a mechanical system, the ABS motor fails after use and we get the dreaded ABS light, Stability control light and cruise control light . also , battery doesnt charge on braking so you get less fuel mileage !
the system on my aqua failed at 225,000km / - after nearly six years of use.

i have debated this issue with many. some blame it on brake oil, some on brake replacement job not done properly, etc
my take is that this is a serial defect and fails rather early by toyota standards

OK, how to fix this

very simple . just get the ABS pump and Brake booster pump assy replaced . you will need to replace BOTH systems .
call me for details . i got my system replaced from an excellent mechanic in lahore , model town. the gentleman imports the ABS pump from japan and doesnt do the kabli work

DM me for assistance . telegram ID = @Blueazure4u

https://tinypic.host/image/WhatsApp-Image-2023-07-13-at-15.43.40.2O6xX
^^ the ABS motor and brake booster assy

[Hassan1991]

gentleman imports the ABS pump from japan and doesnt do the kabli work

He imported brand new ABS motor?

[capsat]

imports the ABS pump from japan

import - legal or grey channel ?

[crema]

I would like to discuss about point A and B mentioned in the title post.

It is mentioned that ABS pump operates the Anti Lock and Stability/TRC algorithms. Which I believe is not correct. The algorithm is written in the non volatile memory of the various control units embedded in the car such as ECU, BCU, Braking Control Units to name some.

The inputs from wheels and body sensors including yaw/G-force and acceleration sensors let the Control Units to decide the right algorithm and action to keep the car in control. The output of this processing is given to ABS motor and the plethora of solenoids to work in conjunction and keep the car stable by providing the hydraulic brake pressure to the required wheels to keep them skid free and planted when required.

At point C it is mentioned that ABS pump harnesses the Energy at deceleration.

As per hybrid Toyota's design it is the MG2 (Motor Generator 2 in Toyota vocabulary) which do this work as it takes the kinetic energy from the moving wheels and in lay man's term the magnetic friction in the motor genereates the electric current to be saved in form on energy in the battery bank. This energy conversion lets the wheel to lose angular momentum and the car slows down.

The reason for their failure on high mileage will lead to JDM blasphemy hence I will refrain from such act.

[crema]

gentleman imports the ABS pump from japan and doesnt do the kabli work

He imported brand new ABS motor?

This thread appears to pitch in high end add with low level of tech research.

[blueazure]

1.assuming that only the ECU contains any chipset to hold control laws is a mistake . the ECU manages the engine and sensor inputs. the relevant control algos are in the sub control units . when the ABS system fails, cruise, TC and lights BLINK. this is called Redundancy in engineering terms. you dont put everything in one sytstem

1. point C - energy from decelaration is two types - without breaking and normal pedal off charging is done via the MG2 system while brake charging is done via the ABS motor . when my system failed, i could only get MG2 charging and not the brake pedal press charging ,

[blueazure]

i dont represent any interests - im just an end user -

please take your internet- research -into -ABS sarcasm else where . im control systems engineer myself and know a thing or two hybrid vehicles

[blueazure]

japan auction imports -

i can tell from the pump operation time that this is a nearly brand new system vs a kabli junk

[blueazure]

does it matter?

[Hassan1991]

It's still used.
The junk in scrap yards also came from same source.

[capsat]

there is nothing manufactured in Kabul, Afghanistan. Every item under the term "Kabuli" is an item from an scrapyard over planet earth. Proclaimed Self Import is a grey channel & 97% used items. Legal Import means an invoice, payment of customs with proof of payment abroad & local.

just like over hyped term self-import JDM, till year 2018.

does it matter?

yes just like 'Smuggled or Imported' rubber tyres for vehicle.
-

[crema]

You can revisit my earlier reply, I have not mentioned single ECU, but have covered all necessary units. Here you have to mind that braking control function do not have redundancy in body control module or in ECU. Rather it works in conjuction with other control units.

For example you will find a pressure sensor in the diaphram assembly. The output of this pressure reading is used by both ABS module as well as ECU. Where ECU helps to maintain the required pressures by moderating the engine RPM when needed in various TRC scenarios.

Regarding MG2 can you school us more about your text "brake pedal press charging" before any non sarcastic comment pops over your control system engeering study.

[Mun33b]

Huh? care to explain how tiny ABS motor is used for recharging the battery? its not even mechanically connected.

[sardarg]

sir @Mun33b this article is quiet interesting for ABS in Hybrid vehicles

[Mun33b]

Brother the link you gave is informative, and covers how ABS is affected by a weak battery, but does not mention any thing about Hybrid battery being charged via ABS (and I know you didnt intend for that aswell).

[capsat]

Hybrid battery being charged via ABS

Regenerative Braking is the term used in HV Battery charging for hybrids, while braking.

[Mun33b]

Yeah but regenerative braking is done via the traction motor present inside the invertor/transmission housing (acting as generator). A gentlemen above mentioned that thats rather done via ABS motor, Im curious to know how.

[capsat]

don't take such 'GURUS' with least idea of IMPORT & OEM NEW with SCRAP smuggled used item from an unknown 3rd party seriously,. Such skilled members' are Thief's dream

[ammarismat]

Share your the mechanic name and number pls