# The most useless accessory in my car is now even more useless **URL:** \ **Category:** Miscellaneous and Personal Stuff I Must Share\ **Created:** [March 3, 2012, 1:54am UTC](https://boards.straightdope.com/t/the-most-useless-accessory-in-my-car-is-now-even-more-useless/614612 "2012-03-03T01:54:47Z")\ **Posts on this page:** 20\ **Page:** 6
**Author:** ![hajario](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/hajario/32/171_2.png) [@hajario](https://boards.straightdope.com/u/hajario)\ **Post date:** [December 30, 2015, 11:57am UTC](https://boards.straightdope.com/t/the-most-useless-accessory-in-my-car-is-now-even-more-useless/614612/101 "2015-12-30T11:57:49Z")
> [@robardin](#): > > Yeah, i think it was unnecessarily vicious. In context it should be obvious he meant “design defect” as “OEM programming bug” here, not “safety recall / lawsuit material”, and his second post said as much. Programmers consider software algorithms “design” too, it’s not a purely structural or mechanical term. And obviously a date counter error going off the rails approximately every 4 years would just get reset and not taken up with Hyundai. > > I do wonder whether this was a problem specific to the unit or a design problem with the unit, because if it was just this one, it would be a really unlikely physical flaw leading to so subtle and specific a behavior. Almost as funny as the result. “Aha, this short right here changed a 1 to a 0, which means this embedded subroutine’s condition is always false, …” > > Most likely it is a programming bug, in which case, has anyone else with a similar vintage Hyundai ever noticed it? Heck, if i ordered the OEM part could I reproduce it? LOL! I’m a hardware guy who works closely with software people and I totally agree with all of this. ---
**Author:** ![davidm](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/davidm/32/225_2.png) [@davidm](https://boards.straightdope.com/u/davidm)\ **Post date:** [December 30, 2015, 1:22pm UTC](https://boards.straightdope.com/t/the-most-useless-accessory-in-my-car-is-now-even-more-useless/614612/102 "2015-12-30T13:22:48Z")
Thanks guys. I was starting to wonder if I was off base somehow, considering the responses I got to a simple opinion. A physical flaw in a single unit leading to a boundary error like this, and apparently not causing any other problems, seems pretty damned unlikely. Feb. 29 is a special case that requires special handling and this is exactly the sort of error you’d see if there was an error in that code. It’s also the type of thing that could be neglected during testing. It is possible that this wasn’t occurring in every car of that model. The manufacturer of that clock unit could have corrected the error at some point and this particular car could have gotten one of the last few of the bad batch, or Hyundai could have changed suppliers partway through the model year. For all we know, **Shoeless** may not be the first owner and the clock could be an accessory added by a previous owner. ---
**Author:** ![hajario](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/hajario/32/171_2.png) [@hajario](https://boards.straightdope.com/u/hajario)\ **Post date:** [December 30, 2015, 1:24pm UTC](https://boards.straightdope.com/t/the-most-useless-accessory-in-my-car-is-now-even-more-useless/614612/103 "2015-12-30T13:24:25Z")
Here is someone else reporting the same thing on Reddit. [https://www.reddit.com/r/mildlyinteresting/comments/20ekgp/my\_friends\_car\_refuses\_to\_acknowledge\_the\_month/](https://www.reddit.com/r/mildlyinteresting/comments/20ekgp/my_friends_car_refuses_to_acknowledge_the_month/) I’ve been in manufacturing for over 25 years and have worked on subcomponents for the automotive industry for over 10 years. That component was made by some subsupplier and could easily has a software bug that was fixed at some point in the run. It’s not a safety issue and almost no one would give a shit enough to complain to the dealer. ---
**Author:** ![hajario](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/hajario/32/171_2.png) [@hajario](https://boards.straightdope.com/u/hajario)\ **Post date:** [December 30, 2015, 1:29pm UTC](https://boards.straightdope.com/t/the-most-useless-accessory-in-my-car-is-now-even-more-useless/614612/104 "2015-12-30T13:29:44Z")
Sorry for the double post but the car is identified as a Hyundai Santa Fe. [https://www.reddit.com/r/mildlyinteresting/comments/20ekgp/my\_friends\_car\_refuses\_to\_acknowledge\_the\_month/cg2nuhc?context=3](https://www.reddit.com/r/mildlyinteresting/comments/20ekgp/my_friends_car_refuses_to_acknowledge_the_month/cg2nuhc?context=3) ---
**Author:** ![hajario](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/hajario/32/171_2.png) [@hajario](https://boards.straightdope.com/u/hajario)\ **Post date:** [December 30, 2015, 1:32pm UTC](https://boards.straightdope.com/t/the-most-useless-accessory-in-my-car-is-now-even-more-useless/614612/105 "2015-12-30T13:32:13Z")
This is fun. One more from a Hyundai forum in 2005. > **[Calendar display in Sante Fe](https://www.thehyundaiforums.com/threads/calendar-display-in-sante-fe.1934/)** > > Part way through March we noticed that the calendar was displaying Feb 47. > We reset it to the correct date and it's ticked over since. As we are now... ---
**Author:** ![robardin](https://avatars.discourse-cdn.com/v4/letter/r/43a26b/32.png) [@robardin](https://boards.straightdope.com/u/robardin)\ **Post date:** [December 30, 2015, 2:02pm UTC](https://boards.straightdope.com/t/the-most-useless-accessory-in-my-car-is-now-even-more-useless/614612/106 "2015-12-30T14:02:20Z")
> [@davidm](#): > > It is possible that this wasn’t occurring in every car of that model. The manufacturer of that clock unit could have corrected the error at some point and this particular car could have gotten one of the last few of the bad batch, or Hyundai could have changed suppliers partway through the model year. > > For all we know, **Shoeless** may not be the first owner and the clock could be an accessory added by a previous owner. Now that last suggestion would be funny too. A useless accessory, that has a bug in it making it even less useful, that was an aftermarket purchase by some schmo who really wanted to see the date at a glance. But not for time travel purposes, as there is no year display. ---
**Author:** ![davidm](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/davidm/32/225_2.png) [@davidm](https://boards.straightdope.com/u/davidm)\ **Post date:** [December 30, 2015, 2:40pm UTC](https://boards.straightdope.com/t/the-most-useless-accessory-in-my-car-is-now-even-more-useless/614612/107 "2015-12-30T14:40:31Z")
> [@robardin](#): > > Now that last suggestion would be funny too. A useless accessory, that has a bug in it making it even less useful, that was an aftermarket purchase by some schmo who really wanted to see the date at a glance. But not for time travel purposes, as there is no year display. It all depends on where this date thing is placed. It could be an incidental part of some other more useful thing. For example, is it part of a map light unit that needed to be replaced at some point and was ordered from a J. C. Whitney catalog? Obviously, from **hajario’s** links, this was a factory accessory, but it’s not unimaginable that someone could have added such a thing. ---
**Author:** ![zut](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/zut/32/2875_2.png) [@zut](https://boards.straightdope.com/u/zut)\ **Post date:** [December 30, 2015, 2:51pm UTC](https://boards.straightdope.com/t/the-most-useless-accessory-in-my-car-is-now-even-more-useless/614612/108 "2015-12-30T14:51:37Z")
There’s a Technical Service Bulletin on the problem, too: > [@](#): > > TSB #0490007 > NHTSA ID #10006732 > Date Announced:APRIL 01 2004 > Summary: THE OPTIONAL ELECTRONIC CALENDAR ON THE OVERHEAD CONSOLE MAY NOT DISPLAY THE CORRECT DATE AFTER FEBRUARY 29TH OF A LEAP YEAR. \*TT So it’s obviously known to the manufacturer - and whether it’s a “design defect” or a mis-manufactured part, it’s unlikely to be a one-off problem. [ETA: April Fool’s Day, heh.] ---
**Author:** ![davidm](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/davidm/32/225_2.png) [@davidm](https://boards.straightdope.com/u/davidm)\ **Post date:** [December 30, 2015, 4:42pm UTC](https://boards.straightdope.com/t/the-most-useless-accessory-in-my-car-is-now-even-more-useless/614612/109 "2015-12-30T16:42:59Z")
> [@hajario](#): > > This is fun. One more from a Hyundai forum in 2005. > > [Calendar display in Sante Fe | Hyundai Forums](http://www.thehyundaiforums.com/threads/calendar-display-in-sante-fe.1934/) And 2005 wasn’t a leap year. Maybe someone reset it with the wrong year at some point. ---
**Author:** ![Dead\_Cat](https://avatars.discourse-cdn.com/v4/letter/d/9fc29f/32.png) [@Dead\_Cat](https://boards.straightdope.com/u/Dead_Cat)\ **Post date:** [December 30, 2015, 5:59pm UTC](https://boards.straightdope.com/t/the-most-useless-accessory-in-my-car-is-now-even-more-useless/614612/110 "2015-12-30T17:59:07Z")
> [@davidm](#): > > Thanks guys. I was starting to wonder if I was off base somehow, considering the responses I got to a simple opinion. Actually I thought your calm and polite response to some uncalled-for snark was really classy. I’m not sure why **Rick** got so upset - in my experience he’s a great poster and a real asset to the SDMB, so let’s hope he was just having a bad day. ---
**Author:** ![hajario](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/hajario/32/171_2.png) [@hajario](https://boards.straightdope.com/u/hajario)\ **Post date:** [December 30, 2015, 6:02pm UTC](https://boards.straightdope.com/t/the-most-useless-accessory-in-my-car-is-now-even-more-useless/614612/111 "2015-12-30T18:02:50Z")
> [@Dead\_Cat](#): > > Actually I thought your calm and polite response to some uncalled-for snark was really classy. I’m not sure why **Rick** got so upset - in my experience he’s a great poster and a real asset to the SDMB, so let’s hope he was just having a bad day. I agree. That was totally out of character for **Rick**. ---
**Author:** ![steronz](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/steronz/32/11765_2.png) [@steronz](https://boards.straightdope.com/u/steronz)\ **Post date:** [December 30, 2015, 6:40pm UTC](https://boards.straightdope.com/t/the-most-useless-accessory-in-my-car-is-now-even-more-useless/614612/112 "2015-12-30T18:40:12Z")
> [@zut](#): > > There’s a Technical Service Bulletin on the problem, too: > > So it’s obviously known to the manufacturer - and whether it’s a “design defect” or a mis-manufactured part, it’s unlikely to be a one-off problem. > [ETA: April Fool’s Day, heh.] Oh man. I mean, I’m a big fan of Rick as a poster as well, but I’m also a big fan of pwnage, and after that speech about 100 years of Hyundai experience, the fact that there’s a TSB about this particularly defect is just too much. ---
**Author:** ![davidm](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/davidm/32/225_2.png) [@davidm](https://boards.straightdope.com/u/davidm)\ **Post date:** [December 30, 2015, 7:57pm UTC](https://boards.straightdope.com/t/the-most-useless-accessory-in-my-car-is-now-even-more-useless/614612/113 "2015-12-30T19:57:35Z")
> [@Dead\_Cat](#): > > Actually I thought your calm and polite response to some uncalled-for snark was really classy. I’m not sure why **Rick** got so upset - in my experience he’s a great poster and a real asset to the SDMB, so let’s hope he was just having a bad day. Believe me, I was not feeling calm and polite, especially after his second response. I intentionally did not respond to the second one because my response wouldn’t have been calm and polite. I considered pitting him, but there have been one or two times when I was having a bad day and responded to someone somewhat snarkily when it wasn’t called for (although I don’t think it rose to the same level) so I’m willing to give him the benefit of the doubt here. ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [December 30, 2015, 8:25pm UTC](https://boards.straightdope.com/t/the-most-useless-accessory-in-my-car-is-now-even-more-useless/614612/114 "2015-12-30T20:25:20Z")
My guess is that it’s a combination of poor design and idiosyncratic glitch. A well-designed piece of software will not only give appropriate output given appropriate circumstances, but will also, as much as possible, give appropriate output given inappropriate circumstances. Ideally, the appropriate response should be to fix the inappropriate circumstances, but at the least, it ought to give some sort of error message. So you’ve got a date clock that usually works correctly, even during leap years. But occasionally, something funny happens-- Maybe there was a voltage surge in the power system, or maybe the car was left in the garage for too long and the internal stay-alive battery in the clock got drained too far, or maybe it was just hit by a cosmic ray or something. And, where a well-designed clock would be able to recover from the problem that caused, a poorly-designed clock couldn’t. ---
**Author:** ![davidm](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/davidm/32/225_2.png) [@davidm](https://boards.straightdope.com/u/davidm)\ **Post date:** [December 30, 2015, 8:36pm UTC](https://boards.straightdope.com/t/the-most-useless-accessory-in-my-car-is-now-even-more-useless/614612/115 "2015-12-30T20:36:26Z")
The appropriate response to finding a value outside of acceptable bounds would be something like what some household appliances do, blink zeros or show a “please reset” message or some-such. I suspect that these particular clocks don’t ever work correctly on leap years (there may be some that work because they got units with fixed software). What are the odds that something like a power surge coincided with the rollover from Feb. 29 to Mar. 1, and that it happened in more than one car? ---
**Author:** ![leahcim](https://avatars.discourse-cdn.com/v4/letter/l/b4bc9f/32.png) [@leahcim](https://boards.straightdope.com/u/leahcim)\ **Post date:** [December 30, 2015, 9:13pm UTC](https://boards.straightdope.com/t/the-most-useless-accessory-in-my-car-is-now-even-more-useless/614612/116 "2015-12-30T21:13:00Z")
> [@davidm](#): > > The appropriate response to finding a value outside of acceptable bounds would be something like what some household appliances do, blink zeros or show a “please reset” message or some-such. I would think that in this case, the logic required to correctly identify the error would be barely less complicated than the logic required to correct it. I.e. Code that does “Oh no, it says Feb 30, and Feb only has 29 days! Must report error condition to the user so s/he can reset me!” might as well be code that does “Oh no, it says Feb 30, and Feb only has 29 days this year! It must actually be Mar 1 – let me adjust that and carry on!” ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [December 30, 2015, 9:33pm UTC](https://boards.straightdope.com/t/the-most-useless-accessory-in-my-car-is-now-even-more-useless/614612/117 "2015-12-30T21:33:37Z")
> [@davidm](#): > > A physical flaw in a single unit leading to a boundary error like this, and apparently not causing any other problems, seems pretty damned unlikely. Feb. 29 is a special case that requires special handling and this is exactly the sort of error you’d see if there was an error in that code. It’s also the type of thing that could be neglected during testing. > > It is possible that this wasn’t occurring in every car of that model. The manufacturer of that clock unit could have corrected the error at some point and this particular car could have gotten one of the last few of the bad batch, or Hyundai could have changed suppliers partway through the model year. I concur with your view - this is exactly the sort of thing that happens when a piece of special case handling code has been done wrong for example accidental use of \< when \> was intended, or != when = was intended. If the code for this device resides in flash or EPROM, I guess it’s possible that it could be a one-off glitch that happened either when it was being flashed, or could perhaps be indicative of hardware failure of a single memory location on the chip. An unintended change to a single byte of code could potentially do this, without manifesting in any other kind of adverse effect. ---
**Author:** ![davidm](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/davidm/32/225_2.png) [@davidm](https://boards.straightdope.com/u/davidm)\ **Post date:** [December 30, 2015, 9:38pm UTC](https://boards.straightdope.com/t/the-most-useless-accessory-in-my-car-is-now-even-more-useless/614612/118 "2015-12-30T21:38:27Z")
> [@leahcim](#): > > I would think that in this case, the logic required to correctly identify the error would be barely less complicated than the logic required to correct it. I.e. Code that does “Oh no, it says Feb 30, and Feb only has 29 days! Must report error condition to the user so s/he can reset me!” might as well be code that does “Oh no, it says Feb 30, and Feb only has 29 days this year! It must actually be Mar 1 – let me adjust that and carry on!” The problem with this is that an invalid date could have any number of causes so you can’t say for sure that a value of 2/30 should really be 3/1. When there’s an invalid value the right thing would be to check another source for the correct value rather than trying to deduce it. In this case the easiest second source is the human operator, and the way to access that source is to flash an error message. ---
**Author:** ![davidm](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/davidm/32/225_2.png) [@davidm](https://boards.straightdope.com/u/davidm)\ **Post date:** [December 30, 2015, 9:46pm UTC](https://boards.straightdope.com/t/the-most-useless-accessory-in-my-car-is-now-even-more-useless/614612/119 "2015-12-30T21:46:46Z")
> [@Mangetout](#): > > I concur with your view - this is exactly the sort of thing that happens when a piece of special case handling code has been done wrong for example accidental use of \< when \> was intended, or != when = was intended. > > If the code for this device resides in flash or EPROM, I guess it’s possible that it could be a one-off glitch that happened either when it was being flashed, or could perhaps be indicative of hardware failure of a single memory location on the chip. An unintended change to a single byte of code could potentially do this, without manifesting in any other kind of adverse effect. I know you agree with me and are just giving a possible alternate scenario. Certainly it could be a bad bit that just happens to be in code that only executes once every four years. That’s unlikely but possible. But honestly, if Occam’s razor is applicable anywhere, it’s here. We could also hypothesize that hackers are breaking into just this model car and screwing with the clocks in order to intentionally mess up the handling of leap years. ---
**Author:** ![hajario](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/hajario/32/171_2.png) [@hajario](https://boards.straightdope.com/u/hajario)\ **Post date:** [February 26, 2016, 2:30pm UTC](https://boards.straightdope.com/t/the-most-useless-accessory-in-my-car-is-now-even-more-useless/614612/120 "2016-02-26T14:30:19Z")
Bumping this because the big day is coming up. [Previous page](https://boards.straightdope.com/t/the-most-useless-accessory-in-my-car-is-now-even-more-useless/614612.md?page=5) [Next page](https://boards.straightdope.com/t/the-most-useless-accessory-in-my-car-is-now-even-more-useless/614612.md?page=7)