2021 Mazda CX-30

As reported by others, Engine Malfunction light came on. Car running rough. Mazda dealer says corroded wiring harness and $5k to replace. They bypass the conventional repair and splice it in. Within a hour of driving after pick up, same engine malfunction light and rough running returns. This time they said I need a new transmission. Electrical issues and faulty transmission are both dangerous. With as much posted online regarding the transmission, I would hope to find a recall. $10k in repairs for a barely 4 yr old car!

For 4-5 weeks the car often would not start. Jump the battery and it would start. Run fine 1-2 days then require another jump. At end required jump nearly every time it was to be used. Presently at Mazda dealer. They confirm the problem. They cannot find the cause. Car has been there two weeks. Waiting for assistance from manufacturer. I researched this on the internet. Visited many Mazda forums an 'do it yourself" forums. This seems to be a common problem. NO where have I read about a satisfactory solution. In fact, it sounds like there is none. Dealer's proposal so far has been to replace rear wiring harness at $7000. It sounds to me that there is a manufacturing problem. Who ever heard of a wiring harness go bad? I believe this to be a poor electronic sensor/device, or perhaps poor wiring. Either case it would be the manufacturers fault. And I believe that the manufacturer should repair it at their expense. I grew up in a garage and never heard of anything like this. The car approximately 21000 miles. All of them are easy highway miles with no abuse or offroad/dirt road use. Yesterday my wife heard about a Subaru that was doing the same thing. Maybe someone in Japan is manufacturing faulty parts. If so that is the manufacturers problem, not mine. So far the car has not stalled going down the highway but one drives it with an uneasy feeling. Stopping without warning on the roadway would be very dangerous. Also, one could get stranded in poor conditions or environment, and that makes this a safety issue. I have attached file regarding battery etc. test I performed. These test have been confirmed by the dealer.

The contact owns a 2021 Mazda CX-30. The contact stated while driving 65 MPH, the vehicle stalled. The messages "Engine Malfunction" and "Computer System Issues" were displayed. The contact was able to pull over to the side of the road. Another driver assisted the contact in jumpstarting the vehicle. The contact was able to drive to her friend's residence. The contact then drove to her residence the following day. The contact stated while starting the vehicle, the vehicle jerked and the failure recurred. An unknown dealer was notified of the failure and provided an estimate for a diagnostic test. The vehicle was not diagnosed or repaired. The manufacturer was not notified of the failure. The failure mileage was approximately 30,590.

The car has some .kind of Electric or electronic malfunction that drains the battery and kills it without giving you a warning. I have taking it to a Mazda Dealer to be fix 4 times and they don't seem to be able to fix it.The battery was replaced.twice one by me and the second time by the dealer in an attempt to solve the problem at some point. Unfortunately just yesterday it happened again it had to towed to the Mazda dealer again for the fifth time. I really hope a solution can be found.

The car's battery has failed two times. The second time is after the battery was replaced -- so the problem was with two different batteries. Both times, I had to call & wait for roadside assistance. Dangerous situation. Both times, the car required a jump-start then a full charge. The dealer denies a battery problem or electrical system problem. However, a Mazda Roadside Assistance service provided advised me on 12/3/2022 that the (second) battery was dead and that something in the electrical system is clearly draining the battery. The car is driven every day. *** Several times a week there is a dashboard notice of "low battery risk". *** This has been consistent, starting with the first week of owning the car. It appears that something(s) in the electrical system is draining the battery to the point of failure. The car is 18 months old with @ 16,500 miles driven. It is a 2021 Mazda CX-30 Turbo Premium Plus. It is available for inspection.