Error Messages and Warning Lights in Toyota and Lexus Cars

A Toyota vehicle is considered to be above average in terms of reliability. But modern Toyota and Lexus cars often prove this old belief is wrong. The variety of error messages and warning lights you can see in a Toyota car is just mind-blowing. And sometimes, decoding those messages and lights takes a lot of effort.

This article embraces all common error messages that can be displayed in Lexus and Toyota vehicles and that I've reviewed in this blog. I will also give you links to original articles with wide research on every mentioned message or warning light.

"Lane Departure Alert Malfunction" message in Toyota

So, the "Lane Departure Alert Malfunction" is a very often guest in your Toyota and there are several reasons you can see this on the dash. It means that the smart adaptive cruise control features aren't working.

This may happen because of the blocked camera or radar. Also, faulty connections in the CAN module, camera, or radar may sometimes cause the problem. But, in most cases, this is rather a software glitch. Also, the installation of the tow hitch may trigger this alert along with the Pre-Collision warning.

I would start with resetting the code (by disconnecting the battery for some time) and observing if it comes back. If it does, then you may need professional help with your Toyota.

Lane departure alert malfunction message highlights:

• Common reasons:sensors or camera issues, temporary glitch, control module connection problems
• How to fix:reset the codes, check the sensor area
• Possible consequences:several smart functions won't be working
• Priority level:Low
• Can you drive?Yes
• DIY repair:Posssible
• Repair price range:$0-$450

"Pre-Collision System Malfunction" message in Toyota

Many Toyota and Lexus vehicles are equipped with smart safety features such as pre-collision warning and automatic emergency braking. If you see the "Pre-Collision System Malfunction" error message, it means that those wonderful functions don't work right now in your car.

The problem may be with the sensor, camera, or the 12V battery. It's important to check if the sensors and camera are clean, there are no blockages. Also, you may choose to drive several miles and see if this fixes the issue. Sometimes, the camera or sensor may be fooled by some weather conditions.

Disconnecting the battery for several minutes may do the magic. If nothing helps, you will need professional help with your Toyota. Just take it to the dealership.

Pre-collision system malfunction message highlights:

• Common reasons:sensors or camera issues, 12V battery problems
• How to fix:check the sensor area, disconnect the battery for some time
• Possible consequences:several smart functions won't be working
• Priority level:Low
• Can you drive?Yes
• DIY repair:Possible
• Repair price range:$0-$550

"Parking Support Brake Malfunction" message in Toyota

This is a very strange issue a lot of Tundras had in 2022 and then a lot of other Toyota and Lexus cars also had, just like an infection.

So, the problem appeared to have various culprits. One of the obvious ones is the broken EVAP canister - it wasn't broken by you, it's a Toyota fault and the canister will obviously be replaced under warranty.

Alternatively, there may be a problem with one of the sonars (radar sensors) in any part of your car. They may lose connections, get broken, or just stop working for no reason. Restarting the car may help for some time.

Also, I've seen electrical gremlins causing this error along with the check engine light. You will need to go to the dealer and insist on using several TSBs they have for this error message.

Parking support brake malfunction message highlights:

• Common reasons:radar sensor problems, EVAP canister issues, electrical problems
• How to fix:check the sensor areas, check the EVAP, and take it to the dealer
• Possible consequences:a lot of smart functions won't be available
• Priority level:Low
• Can you drive?Yes
• DIY repair:Impossible
• Repair price range:$150-$500

"Low 12V Battery" message in Toyota

You will most likely see this message in a hybrid Lexus or Toyota vehicle. This means that the driving time you usually give to your car is not enough to charge the 12V battery that has a lot of duties in your vehicle.

Also, this message may come on the dash when your 12V battery is pretty old and is dying. In this case, replacing it is the only option you have. If the battery is younger than 4 years, you may try using a good charger to charge the battery. If it helps you solve the problem for more than a week, then the battery is still good to go.

Interestingly, this error has other wording: "Aux Battery Low". This is just the same problem because the 12V battery is also called auxiliary (or Aux), so the wording depends on the generation of your Toyota.

Low 12V battery message highlights:

• Common reasons:12V battery has low voltage, aux battery is dying
• How to fix:charge the battery, replace the 12V battery
• Possible consequences:car may not start eventually
• Priority level:High
• Can you drive?Yes
• DIY repair:Possible
• Repair price range:$150-$250

"Drive Start Control Malfunction" message in Toyota

When you see the "Drive Start Control Malfunction" in your vehicle, you may also observe the check engine light. Your Toyota may or may not start in this case.

While in most cases, the problem is in the electronic glitch or weak battery, sometimes, this is a more complex problem. For example, I've seen cases when the wheel speed sensor or the gas pedal electronics were the culprits for this issue.

You should start by checking the battery. Check the voltage, disconnect it for some time. If this doesn't help and the message comes back, you may consider reading the codes in various control units. This may help you narrow down the culprit.

Drive start control malfunction message highlights:

• Common reasons:12V battery issues, electronic glitch, various sensors faulty
• How to fix:check the battery, disconnect the battery for some time, read the codes
• Possible consequences:car may not start
• Priority level:High
• Can you drive?Yes, if it starts
• DIY repair:Impossible
• Repair price range:$150-$500

"P Lock Malfunction" message in Toyota

While the "P Lock Malfunction" can actually be a huge problem that is hard to catch, a lot of mechanics will diagnose it as the transmission control unit problem. But don't jump to conclusions and don't waste your money on this.

First of all, check the auxiliary 12V battery. This message very often attacks hybrid cars of Toyota and Lexus and the culprit in most cases is low voltage in the electrical network. Charging or replacing the battery may solve the issue without doing anything else.

This message rarely changes something in your driving. But if you see this, make sure you always use your parking brake when you park your car. Just to stay on the safe side - always make sure your car has no chance to roll back unintentionally.

P lock malfunction message highlights:

• Common reasons:12V battery issues, transmission control unit
• How to fix:check the battery, replace the TCU if needed
• Possible consequences:P lock may not engage when in Park
• Priority level:High
• Can you drive?Yes
• DIY repair:Impossible (if it's not the battery)
• Repair price range:$150-$1,200

"Charging System Malfunction" message in Toyota

The charging system is the equipment in your car that is responsible for charging the battery. It consists of the alternator, voltage regulator, wires, and connections. The alternator is driven by the serpentine belt that's connected to the engine.

So, when you see the "Charging System Malfunction" message in your Toyota or Lexus vehicle, it's pretty obvious that something in this equipment is not as good as you may expect it to be. In most cases, you should check the alternator. But also, the battery may be the culprit for the charging system error message.

That's obvious that if you keep driving like this, your 12V battery will eventually die and you will have to deal with the problem while your car won't start and won't move. So, better deal with it before things go this way.

Charging system malfunction message highlights:

• Common reasons:alternator, voltage regulator, battery, or wiring problems
• How to fix:check the voltage in various scenarios
• Possible consequences:car may refuse to start eventually
• Priority level:High
• Can you drive?Yes
• DIY repair:Possible, but complicated
• Repair price range:$150-$800

"Stop & Start System Malfunction" message in Toyota

So, when you see the "Start & Stop System Malfunction" message, your Toyota or Lexus won't turn off their engine when stopped at the traffic light. It means that you will most likely need to check the battery.

When your 12V battery is low, the system detects this and won't turn the engine off to charge the battery. The error message will come on the dash to let you know that something is wrong with the system and you shouldn't expect the engine to shut off after each stop.

Anyway, there are also other possible issues like an electronic glitch, engine sensors failure, or issues with more complicated things. If the battery is certainly not the culprit, you may need professional help.

Stop & Start system malfunction message highlights:

• Common reasons:12V battery low, one of engine sensors failing, electronic glitch
• How to fix:check the voltage on the battery terminals, disconnect the battery for some time
• Possible consequences:this may lead to total death of the battery
• Priority level:Medium
• Can you drive?Yes
• DIY repair:Possible
• Repair price range:$200-$550

"Check Hybrid System" message in Toyota

This message can only be seen in a hybrid car. Both Toyota and Lexus can show this, and the warning is pretty common. Also, there is no certain reason why "Check Hybrid System" would come on the dash of your car.

In some cases, this can be the 12V battery's fault. When it's low or dead, the car may not start and a certain code will be stored in the ECU that may trigger the check-hybrid warning on the dash.

Alternatively, there may be an electrical problem. For example, one of the dozens of electronic control modules may have been affected by water intrusion. Also, electrical connections may be lost. In this case, you will only need professional help.

Also, when the hybrid battery is about to die, it may also throw a warning about the hybrid system or there may also be the hybrid-battery light illuminating on the dash.

Check hybrid system message highlights:

• Common reasons:12V battery low, connection problems, hybrid battery dying
• How to fix:check the 12V battery, take it in for inspection
• Possible consequences:the vehicle may refuse to start
• Priority level:High
• Can you drive?Yes
• DIY repair:Impossible
• Repair price range:$200-$750

"Brake Override Malfunction" message in Toyota

The brake override function helps you avoid damage if you accidentally press the brake and the gas pedals at the same time. But it usually works to annoy you by throwing various messages that you most likely don't want to read.

If you see "Brake Override Malfunction" in your Toyota, there is a high chance that the brake switch is dead. But there were cases with electronic control modules problems. So, the best choice is to go to the dealer and check if you can repair the problem under warranty.

If this happened to you after you pressed the gas and brake pedals simultaneously, just disconnect the battery for some time to reset the error message and codes.

Brake override malfunction message highlights:

• Common reasons:brake switch dead, electronics issues
• How to fix:take it in for inspection
• Possible consequences:no serious consequences
• Priority level:Low
• Can you drive?Yes
• DIY repair:Impossible
• Repair price range:$150-$300

"EPB Shift Interlock Function Activated" message in Toyota

The EPB Shift Interlock function is one of the useless modern features in a Toyota vehicle with an electronic parking brake. If you see the "EPB Shift Interlock Function Activated" message on the dash of your car, you may be sure that the system is not working properly.

One way to deal with the problem is to deactivate the system and you won't be seeing this message anymore.

But if you often see this warning, it may mean that the voltage in the system is low. I strongly recommend you check the voltage on the battery terminals in various conditions and make sure the battery is alive.

EPB shift interlock function activated message highlights:

• Common reasons:low battery, EPB problems
• How to fix:charge or replace the battery
• Possible consequences:several smart EPB functions may not work
• Priority level:Medium
• Can you drive?Yes
• DIY repair:Possible
• Repair price range:$200-$350

"SRS Airbag System Malfunction" message in Toyota

The SRS control block is located in a pretty bad place in several models of Toyota cars. It's too close to the wireless charger and its waves may significantly affect its work. That's why a lot of Toyota owners have reported the "SRS Airbag System Malfunction" error message.

In some cases, this can happen as a temporary glitch and it goes away after you restart the engine. But, in some cases, the problem is significant and won't allow the safety systems to work well.

You will need to ask for TSBs that have something to do with this message. Also, make sure the dealer checks the wiring that's connected to the SRS control unit.

SRS airbag system malfunction message highlights:

• Common reasons:wiring issues, wireless charger problems
• How to fix:take it in for inspection
• Possible consequences:safety system may not be working
• Priority level:High
• Can you drive?Carefully
• DIY repair:Impossible
• Repair price range:$200-$400

"Grille Shutter Inoperative" message in Toyota

The grille shutter system is pretty reliable in Toyota cars but it's placed in such a location that it's very often attacked by road debris or small stones. This leads to issues that you have to repair and pay for if you don't know about the TSB.

So, there is a bulletin for several Toyota models when they throw the "Grille Shutter Inoperative" message. The TSB number is 0319-17 and you can easily download it online.

This is actually the only known reason for the grille shutter to go completely off. Other than that, there could be some problem in high-mileage cars with the shutter mechanisms but they are very rare now.

Grille shutter inoperative message highlights:

• Common reasons:something stuck in the grille shutter
• How to fix:take it in, there is a TSB
• Possible consequences:no serious consequences
• Priority level:Low
• Can you drive?Yes
• DIY repair:Impossible
• Repair price range:$0-$500

"Hybrid System Stopped, Shift into P" message in Toyota

When you see the "Hybrid System Stopped, Shift into P" message in your Toyota hybrid car, it means that the vehicle decided to leave you stranded. You will not be able to move the car from its place till you actually deal with this problem.

If you are lucky, the problem is with the 12V battery. Just recharge or replace it and the system will come back to normal. Sometimes, even just disconnecting the battery will make the difference and let you drive.

But the problem is also known to be with the winter conditions. Some Toyota hybrid vehicles may randomly show this annoying message under cold temperatures and require hybrid system software updates.

Hybrid system stopped, shift to P message highlights:

• Common reasons:12V battery issues, cold weather software problem
• How to fix:charge or replace the 12V battery, take the vehicle in
• Possible consequences:car won't drive
• Priority level:High
• Can you drive?No
• DIY repair:Impossible
• Repair price range:$250-$600

"EPB Unavailable" message in Toyota

The "EPB Unavailable" message in your Toyota vehicle means that there is a problem with the electronic parking brake. It may not engage or it may have other problems that will seriously affect your driving.

First of all, you need to operate the EPB switch several times to see if something changes. Then, disconnect the battery for several minutes to see if you can clear the error successfully. Check the battery voltage in various conditions - the battery must always be OK for your car to drive well.

If there are issues with the EPB motors or connections, you won't be able to get rid of the problem on your own. Also, the message can have other wording: "EPB Activation Stopped Incompletely". This is the same message just in different words.

EPB unavailable message highlights:

• Common reasons:EPB switch problems, EPB control module glitch, EPB motor problems
• How to fix:play the EPB switch, disconnect the battery for some time
• Possible consequences:EPB may not engage or disengage
• Priority level:High
• Can you drive?Yes
• DIY repair:Impossible
• Repair price range:$150-$950

"AWD System Malfunction, 2WD Mode Engaged" message in Toyota

While the "AWD System Malfunction, 2WD Mode Engaged" error message actually can mean that your Toyota or Lexus has problems with the AWD system, it very often means that there is a certain glitch in the electronic control systems.

What you need to do is to reset the codes by disconnecting the battery for several minutes. If this doesn't help, you may head directly to the dealership and have them inspect the vehicle. Unfortunately, this may be anything in the AWD system.

But before you take your vehicle to a dealer, just check if the electronics issue can be solved by resetting the system.

AWD system malfunction, 2WD mode engaged message highlights:

• Common reasons:electronic control problems, AWD issues
• How to fix:disconnect the battery for some time, take the vehicle in for inspection
• Possible consequences:AWD won't be working
• Priority level:High
• Can you drive?Yes
• DIY repair:Impossible
• Repair price range:$200-$2,000

"Check VSC" message in Toyota

The "Check VSC" warning is very generic and doesn't mean anything in particular. You will have to think about hundreds of reasons, so there is no point in guessing.

VSC stands for Vehicle Stability Control. This light means that there are issues with anything starting with a wheel-speed sensor and finishing with the catalytic converter. Anything can trigger this light.

So, you may do two things: disconnect the battery to clear the codes and see if they come back. And you may also use the code scanner to see which codes trigger the issue. The codes will help you narrow down the problem and see possible reasons.

In some vehicles, you may also see a "Trac Off" warning which means absolutely the same.

Check VSC message highlights:

• Common reasons:issues in stability control function
• How to fix:disconnect the battery for some time, read the codes
• Possible consequences:vehicle's behavior may change
• Priority level:High
• Can you drive?Carefully
• DIY repair:Impossible
• Repair price range:$200-$850

"Traction Control Off" light in Toyota

The traction control light is the car with two lines behind it. This light along with the check engine light means absolutely the same as the previous message that I've described above - the "Trac Off" or "Check VSC" message.

So, I will not spend your time, the solutions are completely the same.

Traction Control Off light highlights:

• Common reasons:issues in traction control function
• How to fix:disconnect the battery for some time, read the codes
• Possible consequences:vehicle's behavior may change
• Priority level:High
• Can you drive?Carefully
• DIY repair:Impossible
• Repair price range:$200-$850

"AT Oil Temp" light in Toyota

The "AT Oil Temp" light may come up because of your transmission slipping heavily or because of the temperature sensor registering a high temp of the transmission fluid.

If you see this light, it's highly recommended to stop your vehicle immediately and turn the engine off. Let it cool down for a while (20-30 minutes) and try driving. If you get the same message after 15 minutes of driving or sooner, there is an actual problem with your transmission.

You can still try driving on your own but be careful - never drive your car when you see this message. Once it pops up, you should stop the car immediately. Otherwise, you risk getting a fatal transmission damage.

AT Oil Temp light highlights:

• Common reasons:AT fluid hot, AT slipping
• How to fix:stop the car, let it cool down, try driving
• Possible consequences:AT fatal failure is possible
• Priority level:High
• Can you drive?Carefully
• DIY repair:Impossible
• Repair price range:$400-$4,500

Coffee Cup warning light in Toyota

The coffee cup warning light means that you are not driving as you usually do. And the vehicle suggests that you are sleepy or extremely exhausted. This warning is pretty annoying, especially when you drive a company fleet car or several people in a family drive a certain Toyota.

But this warning can save your life sometimes because the sensors will feel your drowsiness much earlier than you will and will alert you before you actually lose control of your vehicle.

You can change the settings of this system in the vehicle settings section, so there are ways to set lower sensitivity for the detection of possible sleepiness. Also, you may turn this feature off if you don't want to see the coffee cup warning light anymore.

Coffee cup warning light highlights:

• Common reasons:drowsiness, sleepiness
• How to fix:have a rest, turn the car off and on again
• Possible consequences:driving in this condition may be dangerous
• Priority level:High
• Can you drive?Carefully
• DIY repair:No need to repair
• Repair price range:$0