Mazda 2 Hybrid Speed limit sign alert problem

[Enjay]

I'm sorry, this is likely to be a long explanation because it's not an easy thing to explain.  I have tried searching, but I can't find an answer (again, because it's difficult to describe the problem briefly).

So, anyway, I'm in the UK and I hope that someone here can shed some light on this problem.  I have a Mazda 2 Hybrid and it has the system where the car can read speed signs and display them on the dash and on the HUD.

With speed signs slower than the national speed limit (30, 40 etc) the display shows a normal speed sign if I am going below the speed limit (e.g. a white circle with a black 30 on it and a red ring around the white area for a 30 mph zone).  If I go above the limit for that area, the whole sign changes to red (i.e. a red circle with a white 30 on it).  If for some reason the car has lost track of what speed limit we are in (typically because I have crossed a junction), then it displays (--).

In case that's not clear, I mean like this (pics I found on the internet - not my car)

So far, so good.

However, there is a problem.  I have noticed a couple of times that my car can get semi-stuck thinking that I am in a zone with a lower speed limit than is actually being displayed.  Every time this has happened, it has been when I have been in a car park where the speed limit is quite low (say 5 or 10 mph).  The car correctly reads the sign and displays the speed for the car park.  However, on leaving the car park, things can get messed up.  (I think this maybe happens when there isn't an obvious 30 (or whatever) speed limit sign displayed when the 10 (or whatever) is still active on the car's display.

So, if I enter a 10mph zone, park up, then drive off later and exit the 10mph zone while the dash is showing (--) (i.e. it doesn't know what speed limit we are currently in) the car gets sort of stuck thinking that we are still in a 10mph zone.

When I say "sort of stuck" or "semi-stuck" I mean that if I pass a 30, 40, 50 whatever sign, the car will correctly show that I am in a 30 etc zone, but if I am going above 10mph, it will display the 30 in the "you are speeding" colours, even if I am doing less than 30.

So, I might be in a 30 zone doing 25mph, my car is correctly telling me that I am in a 30 zone, but the display of the 30 sign on the dash is in the red circle, white numbers format instead of the correct white circle, black numbers, red ring format.  If I were to drop my speed to below 10mph, then the display would correctly show the "you're not speeding" colours, but as soon as I go above 10, it goes back to the "you are speeding" colours.

 

I have been able to correct this in the past by driving through a low-speed zone that is configured in such a way to allow me to drive through it and out the other side while the car is still displaying the lower speed limit.  However, I recently went into a car park with a very low limit (5mph) and I can't find anywhere that has a 5mph limit and which allows me to exit to a 30mph sign while the car is still reading 5mph.

So, my car is stuck displaying the numbers on the signs correctly, but showing the signs in the wrong colour, unless I am going less than 5mph.

And when I say stuck, I mean that the car remembers this across driving sessions.  Switching off the car doesn't fix it.  When I restart, the car still thinks its in the weird unsignposted 5mph zone.  I've tried switching off the sign reading system and switching it back on again (including shutting down the car in the middle), I've tried changing the alert settings for the system but, nothing.  The car is stuck.  I know that it's a minor inconvenience, but it is a bit annoying.

Can anyone help with this?  Is there a way to reset the system (preferably just the road sign reading system)?  Is there a firmware update that addresses this?

Thank you for reading and for any help that you are able to give.

[Roy124]

@Enjay a perfect example of how the system works, though you missed the one where it reacts to a slip road or side road sign. 

Given the suggested EU rule change to have cars automatically limited to the correct speed it is clear that there must be significant improvement on signage. 

I wrote to Highways who passed on car park signage.   I wrote to my MP who assured me that mandatory speed control would only be implemented after protracted consultation.  I was much assured bearing in mind he is an MP and will probably be gone tomorrow. 

[Enjay]

Yep, you're right on all counts, especially the MPs. 🤣

I noticed the system picking up speed limits from side roads and slip roads too.  But at least that self-corrects sooner or later.

Imagine if the car slammed on the anchors because I'd passed a 40mph slip road while doing 70 on a dual carriageway! /shudders.

Amusingly, today I went through a village that had a flashing LED sign saying 20 and the car read it as saying 70!

Definitely not a perfect system.

[Cowgirl]

It also get confused and thinks we are I’m kilometres instead of mph!

[Enjay]

Oooh, I've not had that (yet).  Interesting.  I'll keep an eye out for it happening.

[CPN]

1 hour ago, Enjay said:

Definitely not a perfect system.

As you say, not a perfect system and has been commonly reported in a thread on here many times...

[Cyker]

1 hour ago, Cowgirl said:

It also get confused and thinks we are I’m kilometres instead of mph!

This is the exact problem the OP is having - The RSA says e.g. 30 and you're doing 25 but it still shows the red YOU ARE SPEEDING indication.

It's because it thinks the sign is saying 30kph, which is about 18mph, and you're doing 25.

It's a rubbish system and that's just how it is; Toyota have released some firmware updates to try and fix it, but have ignored the obvious fix of locking the sign recognition to whatever units you've set the car to (i.e. mph or kph) and have shown no indication they will look into it any further from the communications I've had with them.

I'm getting really annoyed with the ADAS - I was nearly rear-ended today because a cyclist was coming from my right but stopped at their lights, as expected, and I started to move off as the lights changed, but for some reason the car thought they were crossing in front of me and slammed on the brakes! It's the inconsistency of it that so aggravating, as it's not the first time I've had similar situations with pedestrians and cyclists but this is the first time it's braked so suddenly and harshly out of the blue like that. I was lucky the car behind me was a Yaris Cross as I bet their EAB also triggered and stopped them crashing into me!

It's been some how getting worse lately - The number of false positives I've had in the last month is more than I've had in ages!

I'm all for making cars safer but when the systems are having the opposite effect then they're clearly not fit for purpose!!

[Enjay]

Oh, OK, so it's not remembering the wrong speed, it's switched to the wrong units internally?  I guess I have experienced that problem after all then.

So, if I'm in a 30MPH zone, but the car thinks its a 30KPH sign, it's going to think I'm speeding until I get below 18.6MPH which is 30KPH.  Add in a little bit of a delay in the system and I could easily not see the "not speeding" coloured symbol by 10-12-ish MPH while slowing down.

That is interesting.  It's progress of a sort.  I guess.

I suppose I have to either ignore it or just switch off the visual alerts (which I assume just means it showing the not speeding style of sign all the time).

Definitely useful info.  Thanks.

As for not safer - the lane correction steering "nudging" is definitely in that category for me too.  The fact that I have to switch it off every time I drive, rather than the preference sticking, is annoying.  I live in a rural area and only rarely travel on roads where being kept in lane would be useful.  So, most of the time I don't want it and actually find it borderline dangerous.  e.g. the other day I pulled out to pass a parked car and as I crossed the central white line to do so, the steering tried to nudge me back closer to the car that I was trying to avoid.

[jimaros]

11 hours ago, Cyker said:

This is the exact problem the OP is having - The RSA says e.g. 30 and you're doing 25 but it still shows the red YOU ARE SPEEDING indication.

It's because it thinks the sign is saying 30kph, which is about 18mph, and you're doing 25.

It's a rubbish system and that's just how it is; Toyota have released some firmware updates to try and fix it, but have ignored the obvious fix of locking the sign recognition to whatever units you've set the car to (i.e. mph or kph) and have shown no indication they will look into it any further from the communications I've had with them.

I'm getting really annoyed with the ADAS - I was nearly rear-ended today because a cyclist was coming from my right but stopped at their lights, as expected, and I started to move off as the lights changed, but for some reason the car thought they were crossing in front of me and slammed on the brakes! It's the inconsistency of it that so aggravating, as it's not the first time I've had similar situations with pedestrians and cyclists but this is the first time it's braked so suddenly and harshly out of the blue like that. I was lucky the car behind me was a Yaris Cross as I bet their EAB also triggered and stopped them crashing into me!

It's been some how getting worse lately - The number of false positives I've had in the last month is more than I've had in ages!

I'm all for making cars safer but when the systems are having the opposite effect then they're clearly not fit for purpose!!

😜 🤣😂So how about changing your car from  displaying hands 🤚or ears👂 per hour to something like an actual measuring unit. 

Maybe 🍆 eggplants per minute? 😜🤣😂

[Enjay]

Well, armed with information from you guys, I can confirm that my problem is that the car is doing its background calculations in KPH.

I kept an eye on when the car was showing the red "you're speeding" icons and it tied in with the MPH equivalent of the KPH value for the number on the icon.

I then switched my car to use KPH as its units and (on a quiet piece of road) drove at 30 KPH in a 30MPH zone, 40 KPH in a 40MPH zone etc.  And, yes, the icon colours were the "not speeding" colours below 30/40KPH and "you're speeding" above KPH.

I hoped that switching between KPH and MPH might reset the problem, but, nope. 😞

I guess my assumption about car parks and low speed limits must just have been coincidence for when I noticed it happening or something.

Anyway, thanks to you knowledgeable people, I now at least know why this is happening in my car, even if there doesn't seem to be a solution.  So, for the time being at least, I've switched off the notifications and the system just shows speed signs on the dash/HUD instead of telling me that I'm speeding at 25MPH.

Thank you. 😊

Now, if I can just stop the entertainment system randomly defaulting back to Gracenotes, even when I have the priority set to not be doing that, I'd be more-or-less happy. 🤪