2020 Subaru Ascent: multiple warning lights

Filed Dec 12, 2025 · AK

Vehicle: 2020 Subaru Ascent Issue: Cold weather software glitch If you are operating an Ascent or possibly other Subarus with the CVT in temperatures below -20F be certain to have either a small wrench or the appropriate size socket to loosen the ground clamp on the battery ground cable with you so you can employ what I call the magic Windows fix wherin one completely de-powers the system and reboots it. With all the ridiculous interconnections, if the CVT temperature sensor thinks the tranny is too cold the cars operating system looses it mind and goes completely bonkers. Subaru obviously did no cold weather testing. We have had 2 failures in cold weather. It only happens at temperatures well below the-20F range. The first case happened last year while driving after being stopped for a couple of hours. Everything seemed normal and then suddenly several warning lights came on and all of the safety systems and the eyesight system shut down. The car ran and drove, but none of the associated systems would work. No traction control. No cruise control. Several other systems. The only solution was to disconnect the battery and get this rolling computer to reboot. This was a temporary fix as the condition repeated itself although the car was driveable but with none of the safety systems operational. This year we were out in cold weather, -25 to -32. We went to a place to have lunch and when I went to restart the car the app failed to do so. So I put on all my gear and went out to start it manually. It would not start and all the warning lights were on and the radiator fan was running full tilt at -25F with the car off. I tried twice to get it going by pulling the battery cable to get it to reboot. Evidently when this happens you must leave the battery disconnected long enough (about 5 minutes) for all the capacitors in the electronics to drain. Once restarted, the car drove normally but we did not shut it down for any reason for the rest of the day.

Filed Jun 6, 2024 · Engine · CO

The battery died after two weeks of replacing it, later revealing the alternator failed. Parts are not available, Subaru kept them My safety was at risk because the lights on my dashboard Christmas Tree'd letting me know something was wrong. Within a couple of blocks I had no power steering and was dying on a busy street. The car was so dead that I couldn't even turn on my hazard lights. The car was jumped by Subaru, the tow truck driver left and the car died two blocks later. This time in the middle of the busy street. The vehicle was towed to Subaru who replaced the battery we bought two weeks earlier. We asked if they check the charging system and they said yes. The battery light was on before we left the lot. We made them keep the car so we wouldn't die in the middle of anymore busy streets. Days later they determined it was the alternator. The car had 26,000 miles on it. I don't know what Subaru did with the parts. They said they needed them as it was a warranty replacement. The battery light never came on before the car died. First the Eye Sight Disabled light came on then many lights on the dashboard flashed on. This happened a couple blocks prior to me losing power. I found the first place I could to get off the road. Two weeks prior when the battery died, the eyesight disabled light came on and the battery light. That time I got home and we replaced the battery. Therefore when the eyesight disabled light came on, I knew something was wrong but thought I had time to get out of the way. Then everything died. The worst part is that hazard lights didn't work.

Filed May 10, 2022 · Electrical · ID

Battery died while in idle, unable to restart, constant clicking and beeping. Requires roadside assistance. This is the 3rd time the battery has been dead on this car....First time, shortly after purchase, the dealer replaced the battery, saying it was a battery issue. Second time the car had been parked in the garage, a few months ago, no lights left on. Today, it was idling as I was picking up my kids, it just died. Battery is about a year old. Now all dash lights are just flashing. Will see if there is permanent damage.

Filed Mar 24, 2022 · Electrical, Engine · ID

My Subaru 2020 with 16,000 miles stalled in the middle of driving down the road in Town, I was driving 35 mph when out of nowhere the car stalled. I was able to coast/turn on to a side street. I’m lucky the car had enough momentum to keep going or we would have been hit by traffic as the street we were on is a busy road. The car flashed all the lights when it stalled and refused to crank over, it was low on gas so I called AAA and they brought 5 gallons of gasoline and filled it. The technician then tried to get the vehicle to start but it wouldn’t. Luckily he offered to tow it to my house for free. I have tried multiple times to get the vehicle to start and it wont. It cranks but doesn’t actually move. I don’t know what’s wrong and now I have to have it towed to the the local dealership. This is the second major issue that has happened. The first one was that the transmission failed and with my car having a branded title for being stolen/recovery. Subaru would not replace the transmission at 7,600 miles and I had to find a used one to replace it with. I now just got the recall letter and have messaged Subaru about it.

Filed Jun 10, 2020 · Transmission · 20,000 miles · NC

Fyi: report is being submitted by co-owner in nc. Reported incident occurred in florida. At around 20,000 miles the dashboard lit up like a christmas tree and the vehicle began having acceleration issues. At the end of the commute to work, approx 55 miles, the transmission stopped responding to the accelerator and no gear would engage. Driver was able to coast the remaining 500 meters to work. Car was towed to subaru and after troubleshooting the computer system with subaru of america the technicians and subaru of america decided it was a transmission issue. Transmission was replaced with a new transmission free of charge under warranty. Vehicle is currently being repaired at time of report. Time may tell if this is a more widespread issue or simply a random occurrence.

Filed Feb 10, 2020 · Electrical · 1,014 miles · MT

Purchased new 30 dec 2019. Owned 5+ weeks no issues - drove 07 feb 2020 no drive-ability issues or warning lights, parked as usual in heated garage at home. Went to start 08 feb 2020, when start button pushed, no starting but all the vehicle lights (interior and exterior) flashed brightly and rapidly (3-4 times a second) for about 30 seconds then all electrical inoperative (no lights anywhere, no horn, no starlink activation... Subaru road assistance called & they summoned anderson towing (a local towing company); when jumper cable attached to battery immediately all lights came on brightly and a loud electrical arcing noise occurred and it started. If this total electrical failure had happened during vehicle operation it could have result in catastrophic injury and damage. Took vehicle to local subaru dealership 10 feb 2020 who checked battery and computer trouble codes and found nothing unusual. How is that possible? It was a total electrical failure - jumping the vehicle reminded me of paramedics successfully applying aed paddles to defibrillate a stopped heart. This situation is similar to other complaints noted for this vehicle. This is a potentially very dangerous issue and needs an immediate remedy.