Thousands of Teslas recalled over brake fluid bug Got a Tesla Model X built between 2021 and 2023? The US National Highway Traffic Safety Administration (NHTSA) has said Tesla will recall almost 55,000 vehicles over a brake fluid warning sensor. Tesla submitted a report regarding the issue on October 11 and an acknowledgment was sent out on October 16. Some 54,676 vehicles …
I was taught to check my brake fluid manually. Is that no longer possible on Tesla? (It is well-described in my 2023 Toyota Owner Manual.)
I know that even unto the 1991 Miata there was a float-switch, but that has given trouble, both false alarm and fail to alert (sticky switch or float).
You obviously haven't ever owned a British Leyland car from the 1970's
Or a 1966 Morris Minor. I borrowed my wifes' one day (my Honda was in for a service) and, when I first went to brake, my foot went flat to the floor.. Frantic pumping of the brake pedal eventually resulted in the usual faint rubbing noises and the car eventually came to a stop.
I mentioned it to her - her response? "It does that all the time, I just pump the brake pedel a bit before I drive off"!
The next week it went to the Morris Minor centre in Brislington to have disk brakes fitted on the front. Not had a problem since.
It's still got the orginal engine block and cylinder head. Replaced the crankshaft about 20 years ago. It's got -tive earth conversion, a proper alternator, heated rear *and* front windows and is currently using Mini Metro seats (headrests). It's not converted for unleaded (shortens the valve and crankshaft life) but instead uses an in-line tin device that the fuel flows over on its way to the carb. Seems to work a treat.
> The tank could run low in just a few pedal presses due to the extreme pressure. There aren't many places where failure will only cause a slow leak.
Twice I have had the fun of pedal dropping right to floor, total burst pipe/hose. (Once at the traffic light at the bottom of the hill.)
All pedals drop slowly as the pads wear (drums not so much cuz (self) adjusters). But the volume of the pot is sized larger than the total pad volume so you run out of pad before you normally run out of fluid.
ALL breaks leak. Not so much cuz pressure; they know that and design the seals for the need. But no seal is perfect and over-tight seals make sticky brakes. (I've had that too, 500 miles from home.) The foot-end cylinder (we won't say master) has a little extra capacity to cover expected seepage.
Henry Ford resisted using hydraulic brakes because he thought they were unsafe. He was not wrong, but Lockheed's (and other's) determination and standardized reliability has turned out better than most mechanical brakes (especially on the steerable wheels).
And no, a seepy main cylinder is not illegal. That's where you look when you can't find the leak (on some cars it runs inside and you have to lift the carpet.)
Failure to implement required functionality.
What is clear Tesla set the wrong value in their controller software for some thing as well known and understood as a brake fluid sensor. Which raises questions about their attention to other important operational variables such as their much hyped driver assist features …
// uint8_t brakeFluidStatus = getBrakeFluidStatus(&car);
// if (brakeFluidStatus & BRAKE_FLUID_STATUS_LOW_FLAG) {
// setBrakeFluidLowLight(&car, true);
// }
// ^^ don't bother with the sensor
//
uint32_t timeSinceLastService = getTimeSinceLastService(&car);
if (timeSinceLastService > 94608000) {
// if it has not been serviced in 3 years, just nudge the user to visit one
setBrakeFluidLowLight(&car, true);
if (timeSinceLastService > 126227704) {
// ok this user is taking the piss. Let's set the engine warning light
setEngineFailureLight(&car, true);
}
}
Well they do provide a number of DIY guides for basic maintenance:
https://www.tesla.com/support/do-it-yourself-guides
And a free subscription (aimed at professionals but accessible to everyone) that covers:
Service Manuals
Parts Manuals
Wiring Diagrams and Connector References
Service Bulletins
https://service.tesla.com/docs/Public/service-subscription-faqs/service_subscription_faqs_en-US.pdf
So, yeah, if you are up for it, you can certainly have a go...
I was surprised Teslas had hydraulic brakes :)
I assumed in Musk's best of all possible worlds, the breaking would be all electric - regenerative breaking to slow down and emergency breaking - shove in a pile of amps from the battery to give it a bit of welly. Of course all under the control of the included safety critical software. :)
Drive in a Tesla? Sorry mate I'll stick to my Leyland P76 ;)
Why would the sensor need to go through the computer? Critical safety systems are typically direct-wired, at least in industry, as you can't trust that the computer will respond in time, or correctly. (It usually will, but "usually" isn't good enough for safety systems.) To be fair, this is more of a warning, but it's a "pull over right now" warning.
(Automation engineer, with 1.5 decades experience in instrumentation.)
Hard wired to what exactly?
Teslas don't have little rows of warning lights (or rows of switches).
If you want something displayed to the driver, it has to go on the flat screen. Which means the computer needs to do it...
And this isn't just Teslas any more. Many vehicles basically now have a flat screen display instead of the little rows of lights.
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