Lexus IS 300 h f sport breaks lost

[Elina]

Hello, am new to this forum and writing from Finland. Had this incident and would like to know if I have any fellow members. Was driving an icy, bumpy piece of road (100 mtrs) with some water spots, slow speed and careful driving. Suddenly got pop up hood failure msg. Parked for some hrs, msg was gone. Drove normally few days. On the other day got the pop up hood msg again and I lost my breaks totally = NO brekas at all. Luckily speed was slow and could let car slowly drive before it stopped. Break/ABS msg popped on screen. Turned car off and let it stay for a while. Turned power on, pop up hood msg came on. Breaks were back. Drove approx 1.5 km home and just before parking lost breaks totally again. Anyone experiencing same and has there been factory cal backs on these models? Am waiting mine to be towed to the Lexus maintenance for repair. Kms on my are a bit under 90K. 

With kindest regards Elina from Finland

 

 

[IS300FSPORT]

From reading what you describe if driving on ice & you have lost anti lock braking system (ABS)  may explain you may have gone into a slide making you think you have no brakes but the pedal will usually vibrate when braking on ice. Even though the brakes are electronically assisted, for you to loose the brakes completely you would have to lose hydraulic pressure (loss of brake fluid) brake pedal sinks to the floor. Check your brake disc & pads slider pins etc all moving freely.

Dont be driving it if your brake pedal is dropping to the floor get it towed to a garage. I suspect you have an electric fault, check your Battery terminals are connected properly & have the 12v Battery tested that can throw out random codes when the Battery voltage is low & have your fuses tested check for continuity with a multimeter. 

Thankfully never experienced such an issue but I imagine its rare.

[Elina]

10 hours ago, IS300FSPORT said:

From reading what you describe if driving on ice & you have lost anti lock braking system (ABS)  may explain you may have gone into a slide making you think you have no brakes but the pedal will usually vibrate when braking on ice. Even though the brakes are electronically assisted, for you to loose the brakes completely you would have to lose hydraulic pressure (loss of brake fluid) brake pedal sinks to the floor. Check your brake disc & pads slider pins etc all moving freely.

Dont be driving it if your brake pedal is dropping to the floor get it towed to a garage. I suspect you have an electric fault, check your battery terminals are connected properly & have the 12v battery tested that can throw out random codes when the battery voltage is low & have your fuses tested check for continuity with a multimeter. 

Thankfully never experienced such an issue but I imagine its rare.

Thank You for the reply. The brakes were lost, no pressure. Brakefluid normal, so seems like hydraulic fault, pedal is loose/soft and no braking reaction. Once I get the car to Lexus and find out the fault, am happy to share the information. While driving and losing brakes it is a very scary and dangerous momentum. Had a friend connecting Bosch fault reader into my car and the msgs came. Trying to post pics in next message.

We have been facing pretty cold weather conditions here in Finland, my Battery is though quite new, it was changed 2 yrs ago. 

[IS300FSPORT]

C1256= Accumulator

C1345 = Linear Solenoid Valve Offset Learning Undone

These seem to common codes documented online when the brakes are not bled correctly, for example  on Toyota Prius forums. If your car is under warranty the main dealer should fix it for free otherwise they will try to sell you an actuator/abs pump etc which is not cheap! 

Failing that try to find a Toyota/Lexus specialist with techstream they should be able to perform a calibration/reset once they rule out the issue.

90Km is low mileage for a part to go out.

Pls keep us updated interesting in knowing the issue/fix

[Elina]

5 hours ago, IS300FSPORT said:

C1256= Accumulator

C1345 = Linear Solenoid Valve Offset Learning Undone

These seem to common codes documented online when the brakes are not bled correctly, for example  on Toyota Prius forums. If your car is under warranty the main dealer should fix it for free otherwise they will try to sell you an actuator/abs pump etc which is not cheap! 

Failing that try to find a Toyota/Lexus specialist with techstream they should be able to perform a calibration/reset once they rule out the issue.

90Km is low mileage for a part to go out.

Pls keep us updated interesting in knowing the issue/fix

Thank you again for your prompt reply. Unfortunately no warranty, bought mine used for some years ago from Lexus official importer and used cars company. Originally imported car, one owner, originally from France. My major concern is that even when calibration could be done, if there is a fault in the system/parts, how could I be sure that it would not happen again. I was driving a busy highway just minutes before the fault msgs came up and the brakes were lost. 

Thank you for your replies,  highly appreciated. Will share information on the outcome once I have taken the car to the repair. It is valuable information to all of us IS owners. 

[Elina]

On 2/4/2024 at 6:59 PM, Elina said:

Thank you again for your prompt reply. Unfortunately no warranty, bought mine used for some years ago from Lexus official importer and used cars company. Originally imported car, one owner, originally from France. My major concern is that even when calibration could be done, if there is a fault in the system/parts, how could I be sure that it would not happen again. I was driving a busy highway just minutes before the fault msgs came up and the brakes were lost. 

Thank you for your replies,  highly appreciated. Will share information on the outcome once I have taken the car to the repair. It is valuable information to all of us IS owners.

Just a short note & upd:

Car at Lexus maintenance under inspection and repair, some parts coming, ABS central unit broken. Apologies fellow owners, feeling a bit ashamed; my car is 2015 and not 2014. Lexus told me they're having a "campaign" on fuel pump check ups, read on call back history that this would be related to this. Will upd more once I have the whole outcome clear what is wrong  and why. Car 2015, mileage under 90K and ABS central unit broken. A bit hard to understand and interesting to see what the final outcome will be and will Lexus take any responsibility on the fault or not.

[Jon Dee]

While I have no expert knowledge on the Lexus braking system, it does seem obvious that there was a serious problem with the ABS mechanism. For obvious reasons the ABS is designed to be "fail safe" so that in the event of a problem with the ABS the worst that can happen is that the ABS function is lost. Normal braking without emergency ABS assistance would remain. 

Looking a the operating diagram for a typical ABS system shows that there are a number of control and check valves, plus a pump and accumulator. When the ABS operates these items raise and RELEASE braking pressure. It is therefore possible that if the ABS was to fail while in the release configuration, it would not be possible to pressurise the brake lines by operating the foot pedal. For example, if both the inlet and outlet valves (shown in the attached simplistic diagram) were open at the same time, it would not be possible to apply pressure to operate the brake. And I'm not suggesting that this is actually what happened, just showing that total loss of pressure because of a failure in the ABS system is possible. 

I too will be interested in the cause of failure on your car if the dealership provides the information. 

Cheers...

 

[Paul Brooksbank]

Could it be possible that water has entered one of the brake lines? Freezing and thawing, thus allowing for the failure then reinstatement of the braking.

[Jon Dee]

25 minutes ago, Paul Brooksbank said:

Could it be possible that water has entered one of the brake lines? Freezing and thawing, thus allowing for the failure then reinstatement of the braking.

Theoretically possible but extremely unlikely. Most brake fluids are glycol based and have a nominal freezing point of minus 40 degrees when fresh. They are hygroscopic and can absorb moisture from the air, but braking systems usually have good seals on the caps to minimise exposure to the air. Lastly, brake lines are designed to keep fluid in under high pressure, and if they can keep brake fluid in they will keep water out no problem. 

Cheers...

[Elina]

The campaign Lexus mentioned must be this one. Instead of communicating this as a safety precaution and call back fix, they spoke like this would be an extra service for free from them to me when fixing my brakes issue.

What is the recall on the Lexus 20LA01?

20V-682 / 20TA02, 20LA01 Recall Summary
This can cause an engine stall while driving, increasing the risk of a crash. The low-pressure fuel pump inside the fuel tank may fail.

 

[Elina]

Hello fellow owners, apologies for radio silence. Investigation ongoing, here a short recap until now:

* ABS unit broken, no clue why and what caused it

* Replaced at Lexus maintenance, original part came from Belgium, took longer than expected

* Drove abt a week: check abs, check brake system and pop up hood failure signs came again. Took car back to Lexus, could drive, had brakes.

* Two other parts of brake system broken, now replaced. Still no clue what caused and why

Lexus pretty reluctant to investigate further, got these comments:

* Too old car (less than 9yrs??!) Lifecycle expectation for electric parts (such as ABS unit) is 1-2 yrs (??!!) and manufacturer not investigating old cars nor part

Asked aren't they interested in knowing whether this could be a global security issue, need for call back if something found? No resources they replied.

Car should soon be ready, will write a thorough msg once get the tech data. Am myself going to ctc Lexus Europe and HQ in Japan. Have the broken parts. Have spoken with several parties and everyone is shocked how brakes can totally be lost from this brand, age and mileage car. This should also be an illegal consequence: how these cars have been accepted to European market.

Am myself considering of changing as I felt pretty unsafe when I sat behind the wheel again. I love it, but cannot trust it to be safe. As it now has let me down twice.

Will send an upd asap.

Brgds Elina