2021 Audi Q5 Plug-in Hybrid electrical system problems

“Vehicle Information: 2021 Audi Q5 Component Affected: Electrical System / Electronic Control Unit (Body Control Module / BCM2) Description of Safety Defect: The vehicle suffered a catastrophic failure of the Body Control Module (BCM / BCM2) caused by water ingress originating from a defective rear sunroof drainage tube assembly. The manufacturing failure of the panoramic sunroof drain allows water to pour directly down the vehicle's interior D-pillar. Because of a severe design flaw, Audi positioned this highly critical central electrical computer completely unshielded in the exact cargo cavity where this water runoff pools. When the Body Control Module shorts out due to this water ingress, it creates an immediate and severe safety hazard. The vehicle experiences sudden, unpredictable electrical malfunctions while in motion, including the risk of uncommanded engine shutdown, a total loss of exterior lighting, failure of the central locking safety systems, and a disabled key transponder system. Audi is fully aware of water ingress vulnerabilities affecting central modules in the floorboards and cargo areas of this platform (as evidenced by NHTSA Recall 90S9 for…”

“On 8/3/26, my 2021 Audi Q5 began throwing numerous different malfunction/error alerts and the engine turned off while driving after a bottle of water had partially spilled onto our backseat behind the drivers side. The vehicle was towed to a nearby mechanic who determined that liquid damaged the gateway control module located under the backseat of the vehicle, as the gateway control module is placed in a "protective cover" (an unsealed plastic bag) and that bag visibly had liquid inside of it. We had immediately contacted Audi upon learning of this issue and decided not to move forward with any repairs, but to instead pay out of pocket to have it towed 70 miles to Audi/where we originally purchased the vehicle. This "protective cover" the control module was placed inside was completed as a recall service repair on our vehicle in April of 2022 due to a NHTSA recall announced in December 2021 regarding safety issues in these control modules failing from liquid spills on the backseat. We contacted Audi, explained that liquid had spilled in our backseat and entered the "protective cover" and damaged the control module. They agreed to inspect our vehicle to…”

“If I have a sensor that will malfunction due to water then there should be a water indicator alert. My sunroof vent was blocked and water went into my trunk where the core module is. I had just come to a red light to turn on to a major highway and my car began to smell like fuel. I rolled down the windows and realized the smell was not as strong as inside. The light turned green and as I stepped on the gas the car went into limp mode as I was in the middle of my turn. The power steering then went out in the turn and the wheel yanked to the left and put me half way into the lane next to me. Thankfully no one was there. I had to yank it back to the right to get off of the highway on to the side of the road. I do not think that the power steering should be associated with that module or at least a water indicator sensor should be added. What happens if someone is on the interstate is driving 75 mph and their power steering goes out. It's in the shop and there is no damage other than now I am scared to drive it”

“The contact owns a 2021 Audi Q5. The contact stated that while driving at an undisclosed speed, several unknown warning lights illuminated, and the vehicle stalled. Additionally, the windows independently rolled up and down, and the engine seized. While attempting to start the vehicle, the vehicle failed to start. The contact stated that the failure had occurred three times within five days. The vehicle was towed to the dealer where it was purchased. The failure was diagnosed with a failed gateway control module. The contact was informed that the gateway control module needed to be replaced. The vehicle was being repaired. The contact was informed that the plastic protective bag that covered the gateway control module was filled with water. In addition, the dealer informed the contact that the NHTSA Campaign Number: 21V947000 (Electrical System, Structure); recall repair was performed prior to the contact purchasing the vehicle. The manufacturer was made aware of the failure but provided no assistance. The failure mileage was approximately 37,200.”

“The safety situation happened when my wife's car got stuck while driving at about 25-30 MPH in the middle of the road.Next day At the nearest Audi service center they found that water has gotten into the rear of the trunk and damaged the electronic module which caused the car to stall.The first repair was estimate at 4600 $ .After the repair the car was inoperable.The next repair was estimated at another 4 700 $.After the second repair the car was inoperable again and the service department told me that the car needed to replace the entire transmission .Which they estimated at another 20 000 $. So the total damage is around 30 000$ .I contacted Audi USA about the whole situation when I received a negative message regarding the solution . I would like to point out that up until the moment mentioned we had no problems with the car .After my personal investigation of the problem ,I found that there was a safety recall # 21V-947 for same problem .It was not issued for my car which meets all the criteria.It looks like it was hidden by the manufacturer. Audi distances itself from the whole problem and refuses to cover the costs of the damage.Thank good this happened…”

“Control module located under rear seat became slightly wet from spilled liquid, and failed. Engine and electrical failure as a result of control module failure. Audi refuses to cover damages as warranty period is over. Vehicle design is defective.”