2021 Mazda CX-5 Electrical Problems

The vehicle's Connectivity Master Unit (CMU) suffers from a severe, persistent electronic hardware malfunction that causes the central information display and dashboard telemetry to blink, cycle, and drop signals erratically. This specific hardware architecture failure threatens to corrupt data transmission lines directly connected to the Advanced Driver Assistance System (ADAS), creating an imminent safety risk of unintended automatic emergency braking or false sensor deployment during highway transit. The vehicle utilizes the exact same defective CMU hardware component that the manufacturer has acknowledged and recalled on other model cohorts; however, the manufacturer has explicitly excluded this specific VIN from safety recall eligibility. Diagnostic attempts by the authorized dealer network relied solely on forcing digital software updates that completely failed to correct the core hardware signaling instability, leaving the vehicle un-repaired and presenting an active, unmitigated electrical and safety hazard on public roads.

NHTSA ID

11750866

Incident

Jun 3, 2026

Radio audio randomly stopped working and you have to disconnect the negative or you have to leave the car off essentially all night. It’s definitely unknown issue there’s videos all over YouTube about it and there’s forms on read about it.

NHTSA ID

11699663

Incident

Nov 16, 2025

..... ON AT LEAST 5 SEPERATE OCCASIONS OUR 2021 MAZDA CX5 SUV ACCELERATED TO A HIGH RATE OF SPEED (ON IT'S OWN). IT HAS DONE IT TO MY WIFE AND I BOTH. I CONTACTED TWO DIFFERENT MAZDA SERVICE CENTERS AND WAS ADVISED THEY HAVE NO KNOWLEDGE OF THIS AND THAT THERE ARE NO OPEN RECALLS OR TSB's AND AS INTERMITTENT AS IT IS IT WOULD BE ALMOST IMPOSSIBLE TO DUPLICATE. ON JULY 18TH THE CAR ACCELERATED (ON ITS OWN) AGAIN BUT THIS TIME IT DROVE MY WIFE INTO A TREE AT APROX. 35/40 MPH BREAKING HER RIBS. THE BODY SHOP INFORMED ME THIS MORNING THAT THE CAR IS A TOTAL LOSS. MAZDA NEEDS TO GET TO THE BOTTOM OF THIS AND RESOLVE THIS ISSUE ASAP. THIS TIME IT WAS A TREE, THE NEXT TIME IT MAY BE AT A CROSSWALK OR AT AN INTERSECTION. IT'S JUST A MATER OF TIME UNTIL SOMEONE IS KILLED OR AT THE VERY LEAST BADLY HURT. I DON'T KNOW HOW MAZDA CAN BE UNAWARE OF THIS PROBLEM, IT'S ALL OVER THE INTERNET. OUR BODY SHOP PULLED IT UP ON LINE AND WAS SHOCKED AT THE AMOUNT OF COMPLAINTS/ CONCERNS THAT EXISTED RELATED TO THIS PROBLEM. PLEASE INVESTIGATE THIS BECAUSE THE NEXT PERSON MAY NOT BE AS FORTUNATE. THANK YOU IN ADVANCE.

NHTSA ID

11676813

Incident

Jul 18, 2025

Infotainment system went dark and I cannot get it to come back on. I’ve read that this has been an ongoing issue and is covered in Mazda cx5 models up to 2020 thru a class action lawsuit, but my one is a 2021 (manufactured we’ll before 2021 though) with a virtually identical system.

NHTSA ID

11668480

Incident

Jun 22, 2025

Just got a oil change. Told my battery is almost dead. Upon looking up information I found a letter for recall for 2021 Mazda Cx5 for Dealer Rework 41 telematics communication unit concern. I called the Dealership and they are refusing to fix the problem. Looks like its just a software update is needed. My car only has 24,666 miles and according to the letter should be fixed. [XXX] I bought the car used in April and did a search for recalls prior to buying the car. There is non on Mazda website or vin search. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ID

11618992

Incident

Oct 7, 2024

Screen blank when I am drving a while without any problem. I saw online and many owner have same problem. I followed company and online instruction. the problem could not be solved.

NHTSA ID

11558769

Incident

Dec 5, 2023

Our 2021 Mazda CX-5 infotainment/backup screen went black/blank. I could still hear radio, but when vehicle put in reverse, backup camera not working. Tried a recommended “fix” which was putting vehicle in reverse and pushing down volume knob for 3 seconds which did not work. Turned vehicle off, waited a minute and then restarted but screen still black and backup camera not working. After vehicle sat for approximately 15 minutes, restarted vehicle and system back to normal. Contacted decker and they had no fix. This is the third time this type of incident has occurred since purchasing vehicle in March 2021.

NHTSA ID

11528937

Incident

Jun 25, 2023

I bought a 2021 Mazda CX-5 from Ramsey Mazda of Des Moines, IA. It offered comparable comfort & features. A selling point was the safety features touted by the salesman. Odd things occurred during the first few months but I attributed it to a learning curve. I saw some odd messages but I really did not think it was relevant until June 28, 2022. I was backing out from a parking space. The Blind Spot Monitoring failed to indicate a car approaching from the right that then stopped in my blind spot. I hit the car behind me. Despite the fact, I understand personal responsibility, I never would have had the BSM worked correctly. I dropped the car off on July 15, 2022 to the Ramsey Mazda Service Center after the BSM failure and a Check Engine Light appeared. I already had the Ramsey Mazda Collision Center look at the car and told them of the of the BSM failure. That man doing the estimate said he had heard of those failures before. On July 15, I dropped the car off at the Ramsey Mazda Service Center to look at the BSM, a Check Engine light, the door locks and the hatch opening on its own. I tried to tell the Service Center that there was something severely wrong with the electrical system in this vehicle. I have a witness to its erratic behavior, but I was continually dismissed. There is more wrong now with my car than when I left it with the dealership. They kept my car for 19 days. During the 19 days, I continually had to call and check on the status of my vehicle. Ramsey Mazda was not and is still not initiating conversation with me or responding to voicemails. The manager of the Ramsey Mazda Dealership on Hickman in Des Moines, IA (JD) is supposed to be handling this issue personally with Mazda Corporate because it now “appears” to be affecting multiple systems in his words. Multiple issues include but are not limited to the BSM, Seat Belt notifications, power driver’s seat, camera system, cruise control system, entertainment system, & hands free communications.

NHTSA ID

11481503

Incident

Jun 28, 2022

While beginning to turn into an interstate exit lane, all dashboard lights lit up, the engine died, and the car stopped. Power brakes & steering were inactivated. My husband was able to coast the car to the shoulder. My Mazda app said nothing wrong with car. Waited 3 hours for tow as we were out of state. The Mazda dealership found the high pressure fuel pump to have a malfunction. Two different technicians at the dealership related that Mazda was aware of the issue & had not yet issued a recalled.

NHTSA ID

11475541

Incident

Jul 14, 2022

The contact owns a 2021 Mazda CX5. The contact stated that the fuel gauge was not operating properly. The vehicle was taken to the dealer and the dealer reprogrammed the Transmission Control Unit (TCU). However, the failure recurred. After taking the vehicle back from the dealer, the contact was driving at an undisclosed speed, when the windshield wiper inadvertently engaged, and several unknown warning lights illuminated. Additionally, the headlights inadvertently turned off and the steering wheel pulled the contact's arm down and the vehicle went to the median, running over a metal pole. The cruise control would not deactivate, and the brakes would not engage immediately. No injuries were sustained. A police report was filed. The vehicle was taken to another dealer, Hiley Mazda of Huntsville (6934 Hwy 72 W, Huntsville, AL 35806). The dealer measured the fuel level resistance range of the fuel level sender and informed the contact that the fuel level sending unit needed replacement. The vehicle was not repaired. The manufacturer was not made aware of the failure. The failure mileage was 1,629.

NHTSA ID

11439487

Incident

Nov 5, 2021

Mileage

1,629 mi

The contact owns a 2021 Mazda CX5. The contact stated that after the vehicle was serviced at the dealer under Manufacturer's recall number: SSPC7 for the TCU, the contact was driving at an undisclosed speed, when the "Keyless ignition malfunction" warning light was illuminated. The contact was able to drive to his residence, but when he attempted to turn off the vehicle, the vehicle would not turn off. The contact had to disconnect the fuel pump fuse for the vehicle to turn off. The vehicle would also not turn on when the contact attempted to start the vehicle. The dealer was made aware of the failure and informed the contact to contact the manufacturer for assistance. The vehicle was diagnosed and repaired. The manufacturer was made aware of the failure and informed the contact they would send for a tow truck, but the tow truck never showed up. The failure mileage was approximately 4,400.

NHTSA ID

11435391

Incident

Sep 30, 2021

Mileage

4,400 mi

On 17-MAY-2021 after sitting unused for 1 day my Mazda CX-5, mfg year 2021 with about 1,500 miles did not start. All electrical systems failed, there was no indication of any power present. The vehicle is presently at the dealership it was purchased at about 90 days ago, 495 Mazda in Lowell MA and is available for inspection. The sudden loss of all electrical systems has the potential for stranding the driver and passengers in dangerous locations. The problem has not yet been reproduced. The vehicle has been inspected by the service department of 495 Mazda in Lowell MA who advised they had charged the battery and tested it as ok and offered to return the vehicle to me. There were no warning lights or other indication of this problem. This morning when I called for service, the dealer, 495 Mazda informed me they do not pick up failed automobiles and I should either call Mazda roadside assistance or jump start the car and bring it in. I measured the battery voltage at 2.5 volts and charged it with a high quality battery charger. The car then started. After shutting off the car there was a faint buzzing sound from the engine compartment. I advised the dealer service department of all these details. I would also note that after the car started I measured the battery voltage at over 14 volts proving the charging system works, after shutting off the engine the voltage dropped to 12.1 volts.

NHTSA ID

11417525

Incident

May 17, 2021