Comment by ErroneousBosh
1 day ago
> If your Range Rover breaks down in a field because a sensor in the air suspension noticed a voltage variance...you are stranded until a tow truck takes it to a dealer.
No, you just reset the ECU and get on with your day.
With all due respect, you are confusing a software race condition with a hard fault in a safety critical system.
Resetting the ECU only works if the error is a transient glitch in the code logic. If the failure is a physical sensor reading out of range?
Furthermore, modern automotive architectures store permanent diagnostic trouble codes in non volatile memory specifically to prevent people from "just resetting it" to bypass emissions or safety checks. You cannot clear those with a battery pull. You would need a proprietary manufacturer tool to force a relearn or adaptation.
But more importantly, your argument accepts a terrifying premise. That a 2.5 ton kinetic object moving at highway speeds should have the reliability profile of a consumer router. If I have to treat my vehicle like a frozen windows 98 desktop to get home, the automotive engineering has failed me. Physics doesn't need a reboot.
Yet despite the appliance-ification of cars, they are, on the whole, much safer and quite a bit more reliable than they were decades years ago, despite being forced to work a lot harder for emissions compliance.
It's true that you can't fix them with a spanner, paperclip and pair of tights any more, but it's so much more rare that you have to.
In many ECUs I've worked on, most faults are treated as transient until they're seen across multiple cycles. Resetting often does genuinely help. Sensors do see weird transients and physically impossible values for all sorts of reasons.
> If the failure is a physical sensor reading out of range?
Then you buy a new sensor and put it in, just like you would any other failed part.
> You would need a proprietary manufacturer tool to force a relearn or adaptation.
You can do almost anything you need to do with a non-proprietary Autel tool.
I mean, I get it, the manufacturers are absolutely doing their best these days to lock up repair and maintenance. But so many folks seem to throw their hands up and over-exaggerate the inability to fix modern cars. I've always worked on my own cars, from a 1960 Triumph TR3 to a 2025 Audi A3, and everything in between. Maybe once every four or five years have I hit something where I needed to take the car to the dealer, and that was true in the 1980s as well as today. Repair information for newer cars can be somewhat difficult to obtain (looking squarely at you, BMW) but with a bit of sailing the high seas, you can get all the shop manuals.
> Then you buy a new sensor and put it in, just like you would any other failed part.
In the middle of nowhere?
7 replies →
From experience if the air suspension ECU freaks out over a sensor reading out of range it's either water in one of the connectors, or the sensor is getting a bit worn and you've run it to the far end of its travel.
Getting the vehicle four-square (possibly jacking up the corner with the faulty sensor so it sits about the right height) and resetting the EAS ECU with a diagnostics tool will solve the problem in the short term.
The other thing of course is you can just get it to sit level or at least level-ish, then unplug the ECU, let it complain about some unspecified fault, and drive it without self-levelling until it can be repaired, probably when you're not knee-deep in mud.
[flagged]
Can you please not cross-examine in HN comments? This is in the site guidelines: https://news.ycombinator.com/newsguidelines.html.
We want friendly curious conversation, not questions designed to incriminate or insinuate. You're welcome, of course, to make your substantive points thoughtfully.