For those having Transmission Issues with their CX-5

Tom95134 doesn't have Mazda Radar Cruise control (MRCC) like you do so his situation is totally different from yours. And I could not find any warnings of changing lanes from owner's manual while using MECC other than generic "do not rely completely on the MRCC system...", so what is the fault doing lane changes with MRCC on?

To Tom95134, please file a safety complaint to NHTSA and report this incident to Mazda North American Operations' Customer Experience Center. This may force Mazda to look into the preblem and make some improvement hence may save some lives later.

BTW where does the manual say "NEVER use cruise control in heavy rain"?

see post #2:

http://www.mazdas247.com/forum/showthread.php?123853867-Out-of-Control-Traction-Control
 
I don't think slippery or winding roads = heavy rain. As long as you don't set your curise control speed too fast and in the heavy traffic on the highway, I don't see anything wrong by using cruise control in the heavy rain. Use your own judgment when use the cruise control.

Any "experienced driver" should know that using cruise control on slippery roads is VERY dangerous.
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I don't think slippery or winding roads = heavy rain. As long as you don't set your curise control speed too fast and in the heavy traffic on the highway, I don't see anything wrong by using cruise control in the heavy rain. Use your own judgment when use the cruise control.


In heavy rain your car can hydroplane. With speed control engaged when this happen it could try to accelerate during this period resulting in a spin out.
 
Don't remember which day it was.. but it was the weekend where the Bay Area had heavy rain and strong wind.. and that could be one of the possible causes...
 
In heavy rain your car can hydroplane. With speed control engaged when this happen it could try to accelerate during this period resulting in a spin out.
Heavy rain doesn't necessary cause slippery road condition if the highway has a good drainage system. Hydroplane is caused by water accumulation, faster vehicle speed, and bad tires, not caused by heavy rain itself. Sometimes light drizzle with light amount of oil from exhaust pipe left on the road surface will cause slippery condition too!
 
In heavy rain your car can hydroplane.

True. And while a well built highway can drain relatively well when new, after years of use, wear patterns created standing water that encourage hydroplaning at relatively slow speeds. Even without wear patterns, multi-lane highways are so wide there is never enough slope to totally prevent any car from hydroplaning during hard rains, especially at speeds around 60-70 mph. A lot of this can be mitigated by tires with a lot of tread left and a tread pattern that is especially good at water evacuation. However, in the actual world, most cars don't have ideal tread depth or the best tread patterns for water evaluating.
 
IMO, only a foolish person uses cruise control in traffic or during rain/snow etc and I am trying to be polite. Ed
 
When people used to learn how to drive properly while cruise control was just being developed it was common knowledge to deactivate it during the rain or snow.
 
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Happened to me today on the way to work. Was able to coast it into a turn lane to stop/restart the vehicle. I made it into work, taking it to a dealer this afternoon. It just stopped "pulling" and rev'ed the motor. Not a fun time.

Just so happen to have a blue tooth OBD-II module and torque pro on the S5. I'll try to upload a screen shot.

Codes were a P0847 and P0780. Also the TBS light came on. The tires did not check out as low with my gauge.

2015 CX-5 2.5L Skyactive AWD Grand Touring w/Tech Package. Bought new 5/2014. Slightly over 10K miles. VIN: JM3KE4DY7F0449xxx.


Update: At dealer now. There is a Mazda 6 here that they just had the parts shipped in from Canada to fix the same problem. Service Manager says there are no parts to fix in continental U.S. Service Manager is now on the phone with Mazda USA to figure out what to do with my CX-5.

Update2: No ETA on parts or fix. They didn't have anymore Mazda loaners so I am now driving around in a huge Ford F-150 4 door pickup. It's nice enough but I'm not looking forward to the MPG hit. Plus I haven't driven a full size in years and it's reminding me of why. It's like trying to park a small house.

Update3: Ok, they called me late today, claim it's fixed. I picked it up just before closing after returning the "loaner" F-150.
I could scan in the receipt (all covered under warranty) if someone really want's to see it. For those keeping score the fix as listed was for TSB #05-005/14 & replaced both valve body switches + various filters and fluids.

I guess now I drive it and see how long it'll last. (limb)

Same thing happened to me this week. Started it up in morning and four dash lights came on; engine check, TBS, traction control, AT. Turned engine off and restarted and only engine check light came on solid. It drove fine for four mile trip. Later in day drove three miles and in traffic engine rev'd high and transmission was disengaged. I drifted to curb and turned engine off. Upon restart transmission was okay and went straight to dealer. It had codes; P0847 (transmission pressure switch = low) and P0780 (shift malfunction). I had found a TSB that stated the TCM firmware should be updated if this occurred here and here. Dealership updated TCM firmware and now my CX-5 seems fine.

This TCM firmware update fixes problem for VIN; 2013-2016 CX-5 JM3KE******100001 - 599999

Apparently the transmission fluid pressure sensor can read low due to contamination with age and then computer disengages transmission to prevent damage. The TCM firmware update prevents this from happening by loosening the pressure sensor tolerances. This update appears to have fixed my 2014 CX-5.

UPDATE: After five months the problem has not happened again.
 
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I thought I'd include our experience here, too. 2014 CX-5, GT+tech, ~85k

* Several dash lights (including CEL) lit up right away when the car was turned on.
* Drove normally for about 1/2 mile and came to a stop normally at a light.
* Still in D, the transmission had entirely disengaged (no power at all) when trying to accelerate from the full stop.
* Turned the car off (possibly with it still in D), and then back on again. (Warning lights were still on.)
* Accelerated normally for about 400 ft.
* Then RPMs shot up, the car slowed down, and suddenly felt like it had little or no power. (This sounded like limp mode when my wife described it to me.)
* Very shortly after that (a few seconds), the transmission completely disengaged and she coasted to the side of the road.
* I showed up after that, and the car started normally, but we didn't want to risk pulling it back into traffic at that time/location. We called for a tow, and the tow truck driver drove it up onto the flatbed.

The dealer pulled a few codes (I still need to get them), and updated the PCM per a service bulletin (don't know which one yet). They said they didn't think the update would have fixed the symptom described and they suggested replacing the transmission. That sounded like a pretty big hammer to me because they weren't able to reproduce the problem. They drove it around locally for a couple of weeks (about 40 miles) to see if they could reproduce the problem, with no luck. Now we have it again, and we're trying to keep our drives local until we have a better sense that we're in the clear.

I'm hoping CC58's description is accurate here -- that the TCM update is the fix. (My dealer called it the PCM -- powertrain or transmission, I guess, but it sounds like it's the same thing to me!)
 
Same thing happened to me this week. Started it up in morning and four dash lights came on; engine check, TBS, traction control, AT. Turned engine off and restarted and only engine check light came on solid. It drove fine for four mile trip. Later in day drove three miles and in traffic engine rev'd high and transmission was disengaged. I drifted to curb and turned engine off. Upon restart transmission was okay and went straight to dealer. It had codes; P0847 (transmission pressure switch = low) and P0780 (shift malfunction). I had found a TSB that stated the TCM firmware should be updated if this occurred here and here. Dealership updated TCM firmware and now my CX-5 seems fine.

This TCM firmware update fixes problem for VIN; 2013-2016 CX-5 JM3KE******100001 - 599999

Apparently the transmission fluid pressure sensor can read low due to contamination with age and then computer disengages transmission to prevent damage. The TCM firmware update prevents this from happening by loosening the pressure sensor tolerances. This update appears to have fixed my 2014 CX-5.

UPDATE: After five months the problem has not happened again.

I'm wondering if the occasional fluid change might prevent said contamination of the pressure sensor. I'm also wondering if the contamination might be some sort of residue buildup on the switch from old fluid.
 
I'm wondering if the occasional fluid change might prevent said contamination of the pressure sensor. I'm also wondering if the contamination might be some sort of residue buildup on the switch from old fluid.

My thoughts exactly. I was kind of alluding to that under the transmission fluid analysis thread. Its easier for Mazda to bump the software threshold up on that pressure sensor rather than go, whoops, maybe that fluid isnt lifetime with respect to the transmission components 😂
 
My thoughts exactly. I was kind of alluding to that under the transmission fluid analysis thread. It*s easier for Mazda to bump the software threshold up on that pressure sensor rather than go, whoops, maybe that fluid isn*t lifetime with respect to the transmission components *

Software adjustments are always a cheap out to mechanical problems , and if it is in fact that, then they should recommend a fluid change. This TSB wouldn't have been generated if they hadn't have seen quite a few problems like this.
 
My mazda 3 would downshift if i moved it from A to M with my foot off the accelerator, but keep the current gear if my foot was on the accelerator when switching from A to M. The idea is it assumes that if you are not accelerating that you probably want to engine brake when shifting to M. I havent tried this on my cx5 tho but i assume its the same.
I had a 2007 Mazda 3 hatch where I used manual mode for engine braking all the time and it worked great. Unfortunately Ive tried the same with my 2019 CX-5 and it doesnt really work at all, it barely slows the car down. Maybe safety programming override by the computer or maybe the car is just too heavy for it to be effective.
 
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