2020 Toyota Corolla Engine Problems

Part is the coolant bypass valve. Toyota has been taken to court but dealership claims now that I’m over 100k miles I can’t do it. There was also a second part about 10 years but I wasn’t clear on the details of the outcome. Toyota has acknowledged this issue in court but failed to do so at the customer level in my case. engine light came on at 97k and now I’m at 104k which is over that 100k mark. Issue is I’ve only take my car to Toyota for repairs. They have known about this but failed to repair or notify me of it. I would have immediately brought my car in at 97k if. I had known. This puts not only me but my 3 kids and entire family at risk every time i drive. This is known to the dealership and they been taken to court for failures to notify customers of this known defect. It’s been inspected by Toyota the last time I took it in about a week ago at 104k miles.

NHTSA ID

11755244

Incident

Jul 31, 2026

A message came on the screen saying “engine maintenance required” and it’s not going away. Upon doing a google search, there is a common failure in the cooling system for these cars reported by a lot of owners.

NHTSA ID

11742614

Incident

Jun 6, 2026

The contact owns a 2020 Toyota Corolla. The contact stated that while at a red light, the vehicle shut off with the check engine and several other unknown warning lights illuminated. The vehicle restarted after several attempts. The vehicle was taken to an independent mechanic and the failure was duplicated. The mechanic retrieved DTC: P1603; "Engine Stall History" (ECM recording an unexpected engine shutdown or a communication error with the Transmission Control Module (TCM). The mechanic associated the failure with NHTSA Campaign Number: 20V682000 (Fuel System, Gasoline) and referred the contact to the dealer for assistance. Several dealers were contacted, and the contact was informed that the VIN was not included in the recall. The manufacturer was not notified of the failure. The vehicle was not repaired. The failure mileage was approximately 59,000.

NHTSA ID

11733489

Incident

Apr 1, 2026

Mileage

59,000 mi

Car shows the below message when A/C is turned on: Engine Maintenance Required Visit Your Dealer

NHTSA ID

11729914

Incident

Apr 7, 2026

Engine coolant bypass valve

NHTSA ID

11707273

Incident

Dec 27, 2025

I have experienced a message saying 'Engine Maintenance Required' and after experiencing the same instances as many people have online, it seems the engine coolant bypass valve is faulty and needs to be replaced. No code can be read using a code reader either.

NHTSA ID

11683483

Incident

Aug 20, 2025

Engine Maintenace required light came on. I was told that my coolant bypass valve needed to be replaced. This is happening on all Toyota vehicles from 2018-2024 common issue but the repair to fix something that should be covered under warranty.

NHTSA ID

11679742

Incident

Jul 6, 2025

Coolant Bypass Valve

NHTSA ID

11673798

Incident

Jul 15, 2025

On June 19, 2025, I was driving and out of nowhere, there was a warning notification that said "A warning light was turned on. Would you like to call an operator?" On the digital cluster, there was a message that said "Engine Maintenance Required - Visit Your Dealer. Mileage noted down was 79,632. I asked around for some insight and people are telling me it's the water/coolant bypass valve that's leaking and the Op code is 24TE04R1. Will this be a covered service?

NHTSA ID

11668609

Incident

Jun 19, 2025

The engine maintenance required message appeared on the dash. I was travel from work to home (about 40 miles). I pulled over immediately at a store, left my car and walked over a mile to the mechanic shop down the road (in 95° weather with a knee that has been through 3 surgeries in less than 5 years). The gentleman took me back to my car. Followed me as i took my car back to the repair shop since it was close and did not have any lights on the dash and I was not overheating. He plugged a reader in it and the error was a coolant bypass valve issue (i can't remember the exact verbage). I purchased a replacement valve 6-17-25, along with toyota coolant. I am having to wait and save up the money to have the valve replaced at the shop got the message code from. I can not afford the dealerships cost to replace the valve. The valve and coolant was expensive in itself. I have read many forums and blogs. Toyota knew there was an issue and I am requesting my reimbursement for the cost of replacing a part you knew was faulty.

NHTSA ID

11668341

Incident

Jun 16, 2025

Flow Shut-off Valve Coolant Leak

NHTSA ID

11665916

Incident

Jun 9, 2025

I have an error that appeared displaying “Engine Maintenance Required” after some investigation snd research, I have noticed that this is a common issue associated with the OEM Engine Coolant Bypass Valve. This occurred as I was driving home from work when I was driving down the freeway, I did not run into any obstacles or have an accident, it appeared out of thin air.

NHTSA ID

11662682

Incident

May 22, 2025

unknown. i know that my car was doing fine and then randomly the coolant was low and my car was overheating on my way to work. i have yet to get it fixed, as i dont know how much it could cost me. but i read that 2020-2021 toyota makes were having issues with their coolant.

NHTSA ID

11661991

Incident

May 18, 2025

An engine maintenance required warning popped up. The pop up wasn't going away. My engine sounds louder than usual when turning my A/C on.

NHTSA ID

11661513

Incident

May 14, 2025

I received a "voluntary Customer Support Program" letter from Toyota saying that a small engine coolant leak can occur that "can allow coolant to drip on other parts of the vehicle. This can cause 'Engine Maintenance Required' to be displayed or cause the A/C not to function normally." Then it concludes that repair with a new "flow shut-off valve" will fix the problem, "under the terms of this Customer Support Program." I thought this was a recall and took my car in only to find that they wanted nearly $700 for the repair, because I did not have an extended warranty. When asked whether this could cause a safety problem if unfixed the reply from the Service Advisor was yes -- the coolant leak could potentially cause the engine to seize up on the highway. I was shocked that a defective part in the car I purchased new for $20,000 plus would not be replaced free of charge. I have put less than 16,000 miles on the car and now I find the resale value is essentially zero. And I now may be driving a potentially risky vehicle that could crash or leave me stranded somewhere. I feel there should be a repair at no charge.

NHTSA ID

11659283

Incident

Apr 4, 2025

Car is currently at 56k miles and the "Engine maintenance required" popped up on my dashboard I'm pretty sure this is the engine coolant bypass valve which I read is a constant problem for new toyotas like mine

NHTSA ID

11656924

Incident

Apr 25, 2025

Drive start control malfunction occurred when turning the car on. Second time this has happened. First time was a charcoal canister and engine coolant valve. It was replaced under warranty at 50k miles but now at 96k miles the dealer says it is not covered under the extended warranty. Not sure how this problem happened.

NHTSA ID

11656874

Incident

Apr 23, 2025

Once I parked my car and turned on the A/C a couple mins later I received a warning message on my car screen saying “ Engine Maintenance Required Visit Your Dealer”. After having my car for 4 years I’ve never received this message till now (04/22/25). I thought it was because I needed an oil change but I was wrong because my oil is good. I checked my car and saw that the issue is the “coolant bypass valve”. I don’t even use my car that much for this to happen. I saw this is a common issue with a Toyota Corolla 2020 but the dealership does not want to fix this issue for free.

NHTSA ID

11656209

Incident

Apr 22, 2025

I own a 2020 Toyota Corolla, and without any prior warning, the “Engine Maintenance Required” message appeared on my dashboard at approximately 79,575 miles. There were no unusual symptoms—no overheating, strange noises, or performance issues—before the light turned on. I had my vehicle inspected by Golling Toyota of Warren, where they diagnosed the issue as a faulty Engine Coolant Bypass Valve. I was informed that the valve needed to be replaced and flushed. The total cost of the repair was $932.21, which I had to pay out of pocket. Because the message specifically said “Engine Maintenance Required,” I was concerned that it could be a serious engine issue. Out of caution, I avoided driving the vehicle until it was inspected, as I didn’t know whether it could result in engine damage, performance failure, or a sudden breakdown while on the road. The fear of an unknown engine-related malfunction created a genuine safety concern for me and others —especially since the warning came without any prior symptoms. I later learned that the problem was tied to the Engine Coolant Bypass Valve, which is known to fail prematurely in Toyota vehicles. This failure can affect engine performance and temperature regulation, increasing the risk of engine damage or failure while driving. There is already a class-action lawsuit concerning this issue, yet Toyota has not issued a recall. Owners like myself are being left to pay out of pocket for a known defect that poses real safety risks. I’m submitting this complaint in hopes that Toyota will be held accountable and that the NHTSA will take appropriate action to protect consumers from this recurring and potentially dangerous defect.

NHTSA ID

11652732

Incident

Mar 25, 2025

“Engine maintenance required” alert received, related to a faulty coolant bypass valve which will need replacement. Vehicle is currently at 51,049 miles. Alert message can’t be dismissed from the dashboard. It obstructs a significant portion of the speedometer.

NHTSA ID

11650700

Incident

Mar 24, 2025

Coolant bypass valve broken dealers are charging $800, class action lawsuit pending

NHTSA ID

11648474

Incident

Mar 15, 2025

Engine Maintenance Required displays see dealer displays in Panel. I have taken to my local shop Engine coolant bypass valve replaced. Still having same issue.

NHTSA ID

11646807

Incident

Mar 6, 2025

Valve matic is messed up. According to my research this is a known issue with 2020 Toyota corollas.

NHTSA ID

11640312

Incident

Jan 29, 2025

Vehicle maintenance light won’t turn off, stays off if car started with AC off but comes on and stays on while AC is running. Coolant overflow valve malfunction

NHTSA ID

11638624

Incident

Jan 26, 2025

"Engine maintenance required. Visit dealer" message appeared about 2 years ago. The message appears when I turn on the A/C or heater and will not go away, which affects multiple functions such as speedometer and text function.

NHTSA ID

11635525

Incident

Jan 1, 2023