Ugh. Sudden issues with almost new 2019 CX-5

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2014 & 2019 CX-5 Touring(s)
As some of you know, we just got a second new (2019) CX-5 back in early November. Well a whole series of very weird things have started to go wrong in the past couple of days. All seem to be electronic in nature - I'm guessing one of the major control modules by the random nature of the issues. This is the list of what's happening:
  • Warning messages (and beeps) appear sometimes, may go away after restart and come back after another restart. Include the following (though not all of them all of the time):
    • Front Camera Sensor System Malfunction
    • Smart Brake System Malfunction
    • Forward Smart City Brake Support Malfunction
    • Brake Override System Malfunction
  • The Cruise Control is no longer operational (even when above messages are not showing)
  • Brake Warning Light (idiot light) lit sometimes, not always
  • Check Engine Light lit sometimes (I read the code at one point and it was P0504 -Brake switch A/B correlation)
  • Rear brake Lights flash constantly, about once per second, when parking lights are on - this happens all the time while driving.
  • Occasionally the Automatic transmission does not shift gears properly, sticking in low gear (engine revving) when accelerating, or high gear when slowing. Moving shift lever to manual and back to auto sometimes fixes it for a while.
You can see the weirdness here. It's going into the dealer on Monday. We'll see what they say, but pretty severe infant mortality for a car with ~1000 miles on it. :(
 

Chocolate

Harpy Eagle
V
2019 CX-5 AWD
Sorry to hear. That's obviously unacceptable for a new car. Is this a Hofu or Hiroshima built CX?


I suggest taking videos when these features are acting up if unable to prove to the dealer.

I have the same issue with occasional gear-holding, where it should upshift. Doesn't happen very often, so I am not concerned, so far. This is a potentially updatable with newer PCM software. However, if I wanted a car to last me more than 100,000 miles, I would have bought a Lexus.
 
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V
13' CX-5 and 16' Mazda6 both Touring w/Tech/Bose
Try disconnecting battery for at least 30 mins to reset things.
 

Ronzuki

South Central PA
L
2018 CX5 Touring
V
w/ Pref Pkg
While battery is disconnected, maybe take it out and to a battery dealer for testing. Did the dealer provide you with the battery test results they are supposed to perform pre-delivery. Sounds like a weak battery to me...or compromised (loose) main power connection(s).
 

yrwei52

2016 Mazda CX-5 GT AWD w/Tech Pkg. Plano, TX
Contributor
L
Plano, Texas, USA
V
16 CX-5 GT AWD Tec
As some of you know, we just got a second new (2019) CX-5 back in early November. Well a whole series of very weird things have started to go wrong in the past couple of days. All seem to be electronic in nature - I'm guessing one of the major control modules by the random nature of the issues. This is the list of what's happening:
  • Warning messages (and beeps) appear sometimes, may go away after restart and come back after another restart. Include the following (though not all of them all of the time):
    • Front Camera Sensor System Malfunction
    • Smart Brake System Malfunction
    • Forward Smart City Brake Support Malfunction
    • Brake Override System Malfunction
  • The Cruise Control is no longer operational (even when above messages are not showing)
  • Brake Warning Light (idiot light) lit sometimes, not always
  • Check Engine Light lit sometimes (I read the code at one point and it was P0504 -Brake switch A/B correlation)
  • Rear brake Lights flash constantly, about once per second, when parking lights are on - this happens all the time while driving.
  • Occasionally the Automatic transmission does not shift gears properly, sticking in low gear (engine revving) when accelerating, or high gear when slowing. Moving shift lever to manual and back to auto sometimes fixes it for a while.
You can see the weirdness here. It's going into the dealer on Monday. We'll see what they say, but pretty severe infant mortality for a car with ~1000 miles on it. :(
My guess is your FSC (Forward Sensing Camera) is malfunctioning. I’d just take it to Mazda dealer and ask them to fix it under warranty and not trying to do anything by myself. I also would call Mazda North American Operations and let them know this’s not acceptable for such a new car with only 1K miles!
 
V
Mazda CX-5 GTR
It does suck having these issues with a new car. But, as others have said, that's what warranties are for. Mazda is squarely on the hook to make it right, so I wouldn't mess with it at all...it's 100% their problem, so they'll need to fix it.
 
V
2018 CX-5 Sport
I agree with the guys who said don't disconnect the battery or try to fix it. Let the dealership fix it and give you the reason what was wrong with it.
 
...I have the same issue with occasional gear-holding, where it should upshift. Doesn't happen very often, so I am not concerned, so far. This is a potentially updatable with newer PCM software. However, if I wanted a car to last me more than 100,000 miles, I would have bought a Lexus.
Maybe your occasional gear-holding results from quick acceleration. This can activate AAS mode.

From the owner's manual:
"Active Adaptive Shift (AAS) automatically controls the transaxle shift points... The transaxle may switch to AAS mode when... depressing the accelerator pedal quickly while the selector lever is in the D position... gear shifting could be delayed or not occur, however, this does not indicate a problem..."

My Suggestion: Put the shifter in manual mode during spirited driving. Then you can control the upshifts.
 
V
2014 & 2019 CX-5 Touring(s)
My guess is your FSC (Forward Sensing Camera) is malfunctioning.
I would agree except for the transmission shifting (or not shifting) issue. My first thought that it was something in the braking-related systems that could tie all the other symptoms together, but that shifting issue threw that out the window. Of course it could be two issues and a coincidence.

Maybe your occasional gear-holding results from quick acceleration. This can activate AAS mode.

My Suggestion: Put the shifter in manual mode during spirited driving. Then you can control the upshifts.
Not spirited driving at all. Sedate driving in traffic. Given only 1000 miles on the car I've not been accelerating hard at all while in the run-in period.

With that many issues and being so new I wouldn’t attempt any fixes and get it to the dealer as soon as you can.
Yeah, as I said in the OP, I have an appt for Monday (tomorrow) morning. But I have re-thought the 'disconnecting the battery' idea. That will clear all the codes - and though it may clear the problem, I worry it will only be temporary. So better to leave it as-is for the dealer diagnosis, I think.
 
V
2014 & 2019 CX-5 Touring(s)
OK, well this either sucks or is embarrassing - jury is still out ...

First, the idiot light that was lit (first post) that I thought was just for Brakes, was actually for the Parking Brake. So I tried switching the park brake switch on and then off again. I also swapped the Sylvania LED bulbs I'd put in the rear side/brake lights back out to the original filament bulbs. Unfortunately I didn't do these separately so don't know which of these had the effect, but now when I took the car on a brief drive this afternoon, all is working fine! No warnings/idiot lights/flashing brake lights or transmission shift issues. Hmph. This could be a coincidence, so will drive the car longer (to dinner) tonight and see if it remains OK.

I can't (hopefully) believe that it was the LED brake bulbs that caused this, so am tending to point my finger at the EPB, but we'll see. If it drives OK tonight, I'll cancel the Dealer visit tomorrow and see what happens with the car. After a while I'll put the LED bulbs back in and check those too. Thanks for the responses and ideas so far.

Sigh.
 
V
2019 CX-5 Signature
OK, well this either sucks or is embarrassing - jury is still out ...

First, the idiot light that was lit (first post) that I thought was just for Brakes, was actually for the Parking Brake. So I tried switching the park brake switch on and then off again. I also swapped the Sylvania LED bulbs I'd put in the rear side/brake lights back out to the original filament bulbs. Unfortunately I didn't do these separately so don't know which of these had the effect, but now when I took the car on a brief drive this afternoon, all is working fine! No warnings/idiot lights/flashing brake lights or transmission shift issues. Hmph. This could be a coincidence, so will drive the car longer (to dinner) tonight and see if it remains OK.

I can't (hopefully) believe that it was the LED brake bulbs that caused this, so am tending to point my finger at the EPB, but we'll see. If it drives OK tonight, I'll cancel the Dealer visit tomorrow and see what happens with the car. After a while I'll put the LED bulbs back in and check those too. Thanks for the responses and ideas so far.

Sigh.
What kind of led bulbs were they? Are they 7443A? Maybe the bulbs cause power quality issues and as a result the modules stopped working.
 

Avoidin Deer

Central Virginia
Contributor
V
2019 CX-5 Reserve
  • Warning messages (and beeps) appear sometimes, may go away after restart and come back after another restart. Include the following (though not all of them all of the time):
    • Front Camera Sensor System Malfunction
    • Smart Brake System Malfunction
    • Forward Smart City Brake Support Malfunction
    • Brake Override System Malfunction
  • The Cruise Control is no longer operational (even when above messages are not showing)
This might be due to your freezing rain. Those warnings happen when the camera is obscured by fog/ice/condensation inside/etc. I've had it happen twice: once when I had so much condensation on the inside it was as though I had sprayed the windshield with a hose (weird sequence of events). The next time was just a moderate amount of fogged glass. The warnings went away as I was driving after the conditions cleared.

The Radar Assist Cruise Control might be likewise affected by the ice blocking the radar unit.
 

Ronzuki

South Central PA
L
2018 CX5 Touring
V
w/ Pref Pkg
No 'might be' about any of it. Fact. Ice, fog, hard driving rain... all inclement weather, causes this useless distracted driver assist technology non-sense to become inoperable (unreliable) when you could truly use the 'assistance'...
 
V
2019 Mazda CX-5 GT Reserve
No 'might be' about any of it. Fact. Ice, fog, hard driving rain... all inclement weather, causes this useless distracted driver assist technology non-sense to become inoperable (unreliable) when you could truly use the 'assistance'...
I noticed over the weekend during my first occurrence of driving while snowing that the "rain sensing" wipers perform differently then they do during rain. They don't seem to sweep as frequently as I would like as snow builds up regardless of the sensitivity setting.
 
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