My dealer (Jeff Hass in Houston) says the problem is that the format of the "time messages" that are used by the GPS satellites was changed. And the old CX-9 code doesn't understand the new format. So it can't use (or can't locate) the time in the message in order to set the clock. And it only looks for the "time message" when the battery has been disconnected.

Apparently, Mazda hasn't (and possibly WILL NOT) update their software (especially in an old CS-9) so that it can retrieve the time from the message format now being used by the GPS satellite.

This sounds reasonable. And I can see why Mazda is reluctant to change the CX-9's software, since the change in the format of the message wasn't their fault.

But (as a long-time computer programmer) I suspect that Mazda COULD easily change their software to allow you to manually input the time. Heck, I could probably make the change myself if they would make the source code available (which I suspect won't happen). But even if you could get the code and make the change, there's the problem of re-flashing the modified code into the car's computer.

The real issue is money. Mazda probably out-sourced the code development to someone in India or elsewhere. And Mazda probably signed-off on it long ago. And to get it modified would be a hassle - new agreements, etc, etc.

My plan is to disconnect the battery at exactly 1:00...

PS: I just now got all the interior plastic panels in my 2012 Lexus LS460 for free! They got "sticky" when exposed to Houston summers. So Lexus contacted the owners and replaced all the panels with new ones that can tolerate the heat. And they replaced them free-of-charge. And even in cars (like mine) that had been bought "used"!!! (I bought mine used at a Mercedes dealer). Apparently, Lexus considers it to be their responsibility regardless of when it fails! Now, of course, a Lexus costs a "bit" more than a Mazda. But it's more an issue of attitude than money. I'll be a lifetime Lexus buyer. As for Mazda, this will be the last one...

 

I don't know how this happened. I have lived with the 1:00 battery fix for the last two years. Today I start my 2008 CX9 and realize my clock had changed back to a wrong time. I'm thinking I have disconnect the battery again. I go into the menu and its unbelievable that the clock is now working. I have no idea. New satellite? Pretty crazy!

 

I came here to share the same news. The exact same scenario happened in my CX9 Saturday afternoon. Hopefully whatever changed sticks around!

 

Maybe they have somehow managed to programme a fix & send it out via the GPS signal? Who knows, glad to see people happy with it.

It all goes back to the roll-over of GPS protocol that happens every so many years. Last roll over was April 2019. Any time your system reboots ( ie battery disconnected ) it needs the data in the GPS signal to set the clock. Unfortunately after April 2019, the data was a different format that certain older Satnav units couldn't understand & reset their clocks.


Doctor Google
What does GPS rollover mean?
The Global Positioning System (GPS) Week Number Rollover is a phenomenon that happens every 1024 weeks, which is 19.7 years. The Global Positioning system broadcasts a date, including a weekly counter which is stored in only ten binary digits. The range is therefore 0–1023.

 

That's exactly what happened to me on August 15th too Andy. I was driving up to my friend's cottage and all of a sudden the clock display on my CX-9 changed to the wrong time. But also, prior to this occurrence, on August 8th the clock on the navigation screen suddenly reset itself and started working properly. There was one minot glitch though and that was it was 12 hours ahead. I discovered this by changing the clock to 24H display. I changed the clock display back to 12H and was happy with it. Then yesterday, back to the screwed up time. It is still displayed on the navigation screen though (previously it was not displayed on the navigation screen).

 

I came onto the site today full of excitement because after a couple of years of using the 1:00 reset method, all of the sudden my clock was working correctly yesterday (and today). But now I see that others did the same but eventually broke again. Oh well, I will enjoy it as long as I can - and then go back to the 1:00 reset method. Thanks Guys!

 

my clock was reset correctly by itself this year 2020 but i don’t know when exactely. One day i started the car and i saw that the clock was correct without touching anything.

 

Tony, as you will see earlier in the thread... the only way anyone has found to fix the broken clock is to disconnect the battery and reconnect it at exactly 1pm or 1am. Then it has the correct time until time changes or the battery dies again. As I mentioned, after a few years of this hack, my clock miraculously fixed itself. Of course, it may not last forever!

 

Renate,
I used to do the same to fix the clock (i.e. disconnect and reconnect the battery) and it worked until the day i saw the time on the clock of my GPS instead of --:-- . From now on i will never let my battery dies.