How are reverse backing up sensors supposed to operate?

yrwei52

2016 Mazda CX-5 GT AWD w/Tech Pkg
Contributor
:
Plano, Texas, USA
I understand. I was referring to when the OP backs up, use the mirror. I have used the mirror to back up for decades and still use the mirror until the sensor beeps. It is nice to hear the beep and stop but, to me, not worth having the dash removed.
The problem for OP's rear parking sensors is they beep continuously whenever he shifts the gear to reverse. This is very annoying and he definitely has strong desire to get them fixed.
 
The problem for OP's rear parking sensors is they beep continuously whenever he shifts the gear to reverse. This is very annoying and he definitely has strong desire to get them fixed.

I wonder if the OP turned it off if that would disconnect it? I assume it would.
 

Chocolate

Harpy Eagle
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2019 CX-5 AWD
If it were me, I would not have it repaired. You just hope the dash and panels are reinstalled so you don't develop rattles and strange noises. The sensor is nice but just use your mirror.

Interesting strategy, but it's covered under warranty and presumably the next buyer wants them to work.
 

yrwei52

2016 Mazda CX-5 GT AWD w/Tech Pkg
Contributor
:
Plano, Texas, USA
I wonder if the OP turned it off if that would disconnect it? I assume it would.
It seems OP's rear parking sensors are Mazda's genuine accessory which is like a third-party add-on unit. There's a physical switch usually installed in the trunk area. Yeah OP can turn his annoying malfunctioned rear parking sensors off easily if he can find that on-off switch.
 

Avoidin Deer

Zoom Zoom, baby
Contributor
:
Central Virginia
:
2019 CX-5 Reserve
It seems OP's rear parking sensors are Mazda's genuine accessory which is like a third-party add-on unit. There's a physical switch usually installed in the trunk area. Yeah OP can turn his annoying malfunctioned rear parking sensors off easily if he can find that on-off switch.

I don't understand. I've not heard of a Mazda Genuine Accessory.

Are you saying this is an aftermarket thing different from a factory installed (port/dealer) function that has the On/Off switch in the dash?
 

yrwei52

2016 Mazda CX-5 GT AWD w/Tech Pkg
Contributor
:
Plano, Texas, USA
I don't understand. I've not heard of a Mazda Genuine Accessory.

Are you saying this is an aftermarket thing different from a factory installed (port/dealer) function that has the On/Off switch in the dash?
Mazda factory Front and Rear Parking Sensors are only now available on 2019 CX-5 Signature although they've been available in other regions for many years. The factory Front and Rear Parking Sensors are integrated with Back-Up Camera and Infotainment System. But those Rear-only Parking Sensors are available as Mazda genuine accessory and it's an independent system which is not integrated with Back-Up Camera and Infotainment System. It's like aftermarket parking sensors which can only beeps. OP has a 2018 CX-5, so his Rear Parking Sensors listed on window sticker have to be a Mazda genuine accessory. But this Rear Parking Sensors as the accessory are totally different from factory Front and Rear Parking Sensors.

Here're true factory integrated Front and Rear Parking Sensors and Back-up Camera. The rear parking sensors incorporate with back-up camera on the same screen. The infotainment screen can also display front parking sensors with graph too! Notice even the Back-up Camera function is more sophisticated than ours as it features not only a static blue guideline like us, but also an additional dynamic yellow "predicted" guideline depending on your steering wheel angle!

The front sensors are integrated into the rear camera so it generates an image of the front and back sensors on the screen that drops out at about 3mph. Cars with HID headlights must have headlamp washers but not LEDs, don't ask me why!
The parking sensors show up on the rear camera screen too but no headlight washers and no rear camera washer as you can see!

IMG_2821_zpsssibhuhb.jpg
The front sensors come on automatically immediately after having reversed OR they can be manually operated from a button on the dash. When you drive off they go off at about 5mph or you can push the switch again.
 

Avoidin Deer

Zoom Zoom, baby
Contributor
:
Central Virginia
:
2019 CX-5 Reserve
Interesting.

Again, being new to the brand, I had no idea 2019 was the first year for those.

As always, thanks for the detailed feedback.

So much to learn...
 

Chocolate

Harpy Eagle
:
2019 CX-5 AWD
Notice even the Back-up Camera function is more sophisticated than ours as it features not only a static blue guideline like us, but also an additional dynamic yellow "predicted" guideline depending on your steering wheel angle!

The omission of this feature (across all trim lines) is inexplicable. The backup camera itself is adequate, but low resolution. An area Mazda could improve for sure.
 
:
2019 Mazda CX-5 AWD Grand Touring
Ok, situation is more complex than originally thought. Let me see if I can summarize this short and to the point.

My car has the accessory package rear parking sensors, these were installed after the car was manufacturered, at the dealership when it was brand new.

This rear parking sensor kit package is different than if the rear parking sensors were installed during manufacturing. If they were installed during manufacturing the module would be in a different place, and the wiring would span the length of the car, and the TSB would apply to this type of installation for the fix where they have to track down the wiring interference.

However, because I have the accessory package installed after manufacturing the package is installed differently. The module and wiring is all in the back. Because of this style of installation the likely cause of the problem is a faulty module. This accesory package does have a warranty period, but mine is already past warranty, it's shorter warranty than the car because it's an accessory part.

With this accessory package you cannot just buy specific components, you have to purchase the entire accessory package and re-install it all. That means $600 for me to purchase it, and then have the new stuff replace the old stuff. There just isn't any other option.

So, we decided to just leave it all alone as is. While we could have had it disconnected we were worried the rear cross traffic alert would also then be disabled since it uses the same sensors, which work fine, the sensors are fine, it's just the module. That feature of the car works just fine, so I didn't want to deactivate it and lose it. Therefore, we decided to just leave it all as is. The beeping only happens in reverse, and all it means is my rear parking sensors won't work right, but the rear cross traffic alert still will.

In summary, the problem can be fixed, but it will cost me over $600 to do so therefore I opted to leave it alone for now. If I ever have extra cash in the future I can have the module replace. Right now, it just isn't that big of a deal, and it does not annoy me in any way. It's not like I drive the car in reverse. So not a big deal really, and the option is there in the future if I ever want to fix it if I have extra cash I want to burn.

Cliff Notes:

Because it's an accessory package the rear parking sensors are installed in a different way, and to fix the issue requires buying a new accessory package so the module can be replaced, which would cost a lot of money cause the parts are out of warranty at this time. I decided to leave it alone for now.
 

Avoidin Deer

Zoom Zoom, baby
Contributor
:
Central Virginia
:
2019 CX-5 Reserve
1-So the rear cross traffic alert beeps differently if a car is coming?

2-Did they give you a quote to replace the unit? I asume the $600 does not include labor.

3-A silly question...is the cross traffic alert also a Mazda accessory and not a factory option? That kinda makes no sense to me that they use the same sensors, because my cross traffic alert uses the Blind Spot Monitoring sensors, and I don't have rear parking sensors.

(What a goat rodeo.)
 

shadonoz

SkyActiv Member
Contributor
:
State of Jefferson
:
2017 CX-5 GT AWD+
If it's a different module why not disconnect it and see what happens?
Seems that if you leave it noisy, you will also lose your rear cross traffic alert, since the parking sensors are always squawking when you're in reverse.
 
"My car has the accessory package rear parking sensors, these were installed after the car was manufacturered, at the dealership when it was brand new.

This accessory package does have a warranty period, but mine is already past warranty, it's shorter warranty than the car because it's an accessory part.*

I realize they were installed by a dealer*but were they installed before the car was delivered to the original owner? If the answer is YES, then it would seem to fall under the warranty for accessories as shown below and be covered.

Accessories
Mazda notes that all Genuine Mazda Accessories, if installed by the Mazda Dealer prior to or at initial vehicle retail delivery, carry the same new-vehicle limited warranty as the vehicle.
 
:
2019 Mazda CX-5 AWD Grand Touring
1-So the rear cross traffic alert beeps differently if a car is coming?

2-Did they give you a quote to replace the unit? I asume the $600 does not include labor.

3-A silly question...is the cross traffic alert also a Mazda accessory and not a factory option? That kinda makes no sense to me that they use the same sensors, because my cross traffic alert uses the Blind Spot Monitoring sensors, and I don't have rear parking sensors.

(What a goat rodeo.)

1.) Correct, I get two warning symbols that pop up on the display and the car beeps differently enough over the constant beeping that I can tell the difference, it's a faster kind of beep, and it works just fine.

2.) It's $600 for the kit, and then there would be labor on top of that, I didn't get a quote for the labor, at that point I just decided let's leave it alone for now.

3.) The rear cross traffic alert is a standard feature for the Grand Touring model I think, not an added accessory. You might be right about that, about the sensors using the blind spot monitoring sensors and not the rear parking sensors. I wasn't 100% clear on that, but you are probably right. We concluded that it's best to just leave it as it is for now anyway. Honestly, the beeping isn't that annoying. It's not a big issue to me, and I didn't want them to take apart other things just to see if disconnecting it would disable anything else, best just to not take the chance IMO.

If it's a different module why not disconnect it and see what happens?
Seems that if you leave it noisy, you will also lose your rear cross traffic alert, since the parking sensors are always squawking when you're in reverse.

I just didn't want to take the chance honestly, it would have meant taking parts of the car apart to get to it, and honestly it's just not a big enough issue to me to disable the beeping, the rear cross traffic alert works and I didn't want to take the chance of losing that feature.

"My car has the accessory package rear parking sensors, these were installed after the car was manufacturered, at the dealership when it was brand new.

This accessory package does have a warranty period, but mine is already past warranty, it's shorter warranty than the car because it's an accessory part.*

I realize they were installed by a dealer*but were they installed before the car was delivered to the original owner? If the answer is YES, then it would seem to fall under the warranty for accessories as shown below and be covered.

Accessories
Mazda notes that all Genuine Mazda Accessories, if installed by the Mazda Dealer prior to or at initial vehicle retail delivery, carry the same new-vehicle limited warranty as the vehicle.

I don't know the answer to that honestly. I have no idea who the original owner is or what they did.

At the end of the day, I'm ok with the results, if I ever want to in the future I can have it fixed properly, right now I need to just make my car payments :p

I want to thank everyone for your interest and feedback, at least I'm now informed on the situation.
 
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HardRightEdg

US 2020 CX-5 Touring AWD Soul Red
Related topic in a 2020 Touring:

Until the other day, I've found the Rear Cross Traffic Alert to be the most frequently useful of the safety gadgetry, flawless in picking up vehicles, speeding golf carts, pedestrians from a pretty decent distance away, 30 feet or more on either side. Then this:

I'm pulling out of a parking spot with the often-encountered zero side visibility afforded by an adjacent tall SUV with rear tinted windows. So, I slowly ease out of the spot. I'm approaching a 1/3 of the way out and in the time it took to glance at side clearances some dame had pulled up right behind me, stopped, and laid on the horn. The cross traffic alert did not sound; the sideview mirror alerts did not flash; I came pretty close to hitting her. She pops open her door, looks at the side of her car, doesn't look at me, and heads off. I'm guessing she saw me pulling out and figured I'd stop for her.

A week later I'm pulling out in another lot and it sounded off for a pick-up approaching at an oblique angle from a decent distance away--just like it should.

Has anybody else encountered one-off failures of the system? Any accounting for this one? The offending vehicle was a white SUV on an overcast day, though I can't imagine that has anything to do with a radar-driven system, not a camera-dependent one.
 
:
Southwest Ohio
:
'19 CX-5 diesel
I'm pulling out of a parking spot with the often-encountered zero side visibility afforded by an adjacent tall SUV with rear tinted windows ...
A possibility that comes to mind is that the lady in the white SUV was already there (stationary) in her position so the car didn't sense any movement/approaching vehicle and somehow you didn't notice her there either till she sounded the horn.

That would fit into the puzzle of rear cross traffic alert functioned 100% before and after. Human error. It happens. To us all :) .
 
:
2017 Mazda CX-5 GT, 2016 Mazda6 iGT, 2014 Mazda3 sGT hatchback
From my experience... RCTA does not pick up stationary vehicles (or ones that move slowly).
It relies on Doppler effect to alert drivers.
Same radar sensors are used for BSM, but Doppler effect is not used for that application.
It can pick up vehicles in blind spots of the same speed (relatively stationary).

That makes sense in that, when you back out of your parking space, you don't want the system to pick up parked vehicles, which are everywhere nearby.

The White SUV per se could be moving very slowly at that time when you pulled out of your parking space.
 

HardRightEdg

US 2020 CX-5 Touring AWD Soul Red
A possibility that comes to mind is that the lady in the white SUV was already there (stationary) in her position so the car didn't sense any movement/approaching vehicle and somehow you didn't notice her there either till she sounded the horn.

That would fit into the puzzle of rear cross traffic alert functioned 100% before and after. Human error. It happens. To us all :) .
My "duh" #1:

You are in all likelihood correct. Probably sometime between glancing in the rear view mirror and putting the car in reverse, I took a moment to do something--adjust audio, take off the mask, whatnot--enough time for the SUV to pull up and stop. I had just gotten the Moderna vaccine shot #1 and had been feeling oddly tired. That's my story and I'm sticking to it. ;)
From my experience... RCTA does not pick up stationary vehicles (or ones that move slowly).
It relies on Doppler effect to alert drivers.
Same radar sensors are used for BSM, but Doppler effect is not used for that application.
It can pick up vehicles in blind spots of the same speed (relatively stationary).

That makes sense in that, when you back out of your parking space, you don't want the system to pick up parked vehicles, which are everywhere nearby.

The White SUV per se could be moving very slowly at that time when you pulled out of your parking space.
This takes me to my "duh" #2:

As I read HyFlyer's post I slapped my forehead, figuratively not literally. The Cross Traffic Alert is a motion detector, not an object detector per se, as you say. We know this from daily experience. When backing out to the warning line in the backup display, there's no alert. I've since tried it in my garage with door closed backing a scooch over the line--no alert. No, I did not hit the door. (y)

I suspected from the beginning that the camera stuff and the radar stuff are two different systems that operate independently, doing different things without talking to each other. But a question is begged: why no alert from the camera system if you cross that back line? Seems like a simple thing to do, and a reasonable thing to do given the attention to idiot proofing within the safety systems and convenience automation. Not a complaint, more a curiosity. I admit to occasional idiocy, which should be obvious by now.

Without going back to the manual to parse out which functions are camera driven, which are radar driven, and when alerts can be produced, it might be a case of the camera not interacting with audio from the get go.