To the Toyota owners, you should have come across a C1201 code on the dashboard. Well, do not be confused if you can’t see what this code means, as this article is here to answer those questions: why do I see this code, and how can I do away with it? So first, what’s a C1201 code?
The C1201 code is an error code that signifies your traction control system has an issue. This issue could be caused by anything, especially a faulty brake light switch, mainly because this switch informs your vehicle’s TCS that the brakes have been applied, and should this switch go bad, the error code (C1201) will come up.
What Does the C1201 Code Mean?
When you see the C1201, it means your engine control system has come down with an issue. It works in line with various codes in your car to depict faulty engine parts like the emission system, fuel system, traction control system, and anti-lock brake system to reveal their respective error codes.
Having said that, when a C1201 code pops up, it’s safe to say that a thorough check of the system should be carried out to ascertain the actual problem. Also, be on the lookout for other error codes and fix whatever problems you find because these codes help keep you in the know on the latest car issues.
Also Read: How Long Can I Drive With a Misfiring Cylinder?
What Causes the C1201 Error Code in Toyota?
Though the C1201 code is just as confusing as its cause, it should suffice to know that Toyota has provided a Technical Service Bulletin to help ease your confusion.
According to the technical service bulletin #EG013-03, C1201 could be a result of a leaking gas cap, faulty engine control system, bad brake light switch, a malfunctioning oxygen sensor, or wheel speed.
So let’s find out quickly how the code connects to the possible reasons stated above:
1. Evaporator Emission Control System Leak
When the gas cap isn’t properly tightened, there’s sure to be evaporation which is called (EVECS) Evaporation Emission Control System. In addition, this leak sets off the C1201 error code, which also triggers other codes that will be on our topic of discussion later.
So, this evaporation control system works to regulate the distribution of steam and fumes from the car’s fuel system. This EVAP canister stops the release of vapor into the air by redirecting the vapors into the canister, where they’re then dissolved.
The evaporator emission control system is made up of different components and their respective roles. For instance, the gas cap keeps the vapors from evaporating out of the fuel system.
Now, should the gas cap be slightly opened or not properly threaded, the vapor is released into the air; the evaporation system detects this release and sets off the C1201 error code.
2. Faulty Brake Light Switch
This switch is the one connected to a vehicle’s brake. When the brakes are used, the switch is turned on with the show of a light that signals its activation. This switch is found close to the handlebar or pedal.
When activated, the switch sends a message to the (BCM), the Break Control Module, which then turns on the brake light. The switch doesn’t only activate the brake light but other features like the vehicle stability control or traction control system.
So should this switch go bad, the vehicle stability control and traction control system won’t be activated again? The brake control system may as well not be signaled when you use the brakes; this sets off the C1201 error code.
3. Anti-Lock Brake System Malfunction
This system is a preventive tool that prevents the wheels from closing when you apply the brakes. The anti-lock brake system makes use of a sensor to detect when the wheel is on the verge of being locked up, then uses the brake on the wheel.
Now should this ABS come down with a problem, be sure to encounter the C1201 error code. There are several reasons for a faulty ABS; the first is an anti-lock brake control module, bad sensor, bad ABS pump, anti-lock brake, or low brake fluid.
4. Wet Wheel Speed Sensor
Your ABS uses the speed sensor to detect when the wheel is on the verge of locking up. This sensor is found at the center of your wheel; it also measures the velocity of this wheel.
The C1201 error code will surely pop up if this sensor becomes wet. And wet sensors mostly happen when you come in contact with water or any fluid, especially when you get your car washed or drive into a puddle; it tends to get wet.
5. Faulty Oxygen Sensor
A faulty oxygen sensor surely triggers the code (C1201). And note old, contaminated, or bad connection could result in a faulty oxygen sensor.
Modern vehicles have oxygen sensors to help them improve the mixture of air and fuel. This sensor makes a voltage sign that relates to the number of oxygen within the exhaust channel.
The car’s computer then uses that signal to correct the mixture of air-fuel to improve its performance and reduce fuel consumption.
High fuel consumption, reduced power, and increased emissions could occur if the air and fuel mixture is excessively rich. And if the reverse is the case, the engine could get damaged.
What Are The Symptoms Of A C1201 Error Code?
Why the C1201 code could mean just about anything, this code isn’t going to expose to the signs that your car is experiencing. All this code does is produce a check engine light; other than that, any other symptoms your vehicle is experiencing are the problems listed in the scanner of the code.
Here are the main problems you’ll encounter:
1. Traction Light On
This is the first and most prominent sign of this error code; the traction light comes on, which indicates that the system is down with a problem.
2. Vehicle slipping
You may also discover that your car may begin to slide and slip, especially when you drive on roads that are slippery. This is another sign also that the traction system isn’t working.
3. Brake light not working
If your brake light doesn’t work after applying it, it’s also a sign mostly because of the faulty switch that remotes the brake light.
Also Read: How Long Does It Take To Fix an Evap Leak?
What Harm Can The C1201 Code Toyota Cause?
An unresolved C1201 code can bring about serious damage to your car. Slipping and sliding while driving is one of those problems you’ll encounter, problems that could cause accidents.
The brake light is not coming on when they’ve applied, another problem you’ll encounter. So do not hesitate to fix this code, as this could also cause an accident.
How to Troubleshoot Toyota C1201 Code?
Three similar codes are used to wipe out the C1201 error code. They’re P0455, the code that detects an evaporative emission control system that is an excessive flow or drop amount of flow. While the P0441 code is that code that informs you your vehicle’s evaporation system is experiencing an abnormal purge flow and ECS malfunctions.
The P0455 code means the system is experiencing a gas leak. This leak could be a line close to the vehicle’s filler torque or charcoal container, but it’s usually a gas cap that leaks. And this happens probably because the cap is old or not properly worn.
So to avoid triggering the C1201 error code, the P0455 code should be rectified. Scan tools can be used to check the level of the evaporation system. And should it not function like it ought to, you might need to repair or replace the parts that have been affected.
Beneath the covering of your car, there are a number of sensors and switches that control various parts of the engine’s performance. And when a system or more says “check engine” it’s simply saying there’s a problem with a part or more. For instance, fuel injectors.
This can be resolved by doing away with the P0455 code because it’s usually the bane of the issue.
The C1 code informs the vehicle to activate the “check engine” light and reduce the traction and VSC. Meaning the C1 error code informs you when there’s a problem with the two systems. So to fix this, the PO code should be altered.
How to Fix C1201 Code?
Fixing a C1201 code can be done in several ways, below are the common ways to get it done:
- Tightening and accessing the gas cap that is leaky
- Replacing your gas cap seal
- The ECS should be reset
- The cap of the gas should be replaced with an OEM
- The switch of your brake light should be replaced.
- Bleed the brakes.
- Replace the pump of the ABS
- Attempt performing the zero-point calibration exercise.
- Drain and refill the vehicle’s brake fluid tank
- Change its oxygen sensor
- Troubleshoot and repair the wiring
- As stated above, there’re several ways to fix a C1201 code. Nonetheless, when your vehicle displays this code, it’s advised to take the car to a good engineer or consult your dealer.
Common C1201 Diagnosis Mistakes
When dealing with a C1201 code, most people make the mistake of failing to consider the other error codes. However, forgetting this code won’t diagnose the actual problem. You’d also need to know what it relates to so as to determine its problem.
Here are other codes that relate to the C1201 code:
- P0455: (EVECS) Evaporation Emission Control System detects leaks
- P0441: EVECS wrong purge flow.
- B1604
- B1636
- B2100
- B1300
- B2100
- P1130
- P1340
Recommended Tools for Diagnosis.
- Basic Hand Tools
- Diagnostic OBD Scan Tool
- Electrical Contact Cleaner
- Multimeter
- Vehicle Repair Manual
C1201 Code Toyota Fixing Cost
For this, the repair cost is determined by the cause of the repair. So if it involves replacing your gas cap or tightening it, it’s relatively less expensive. Its price is usually below $20.
But the reverse is the case if your ABS pump is involved or the brakes need bleeding. The cost of changing the ABS pump costs nothing lower than $300.
Oftentimes, there might not even be a need for a replacement. The code usually results from some work on your car or some of the sensors going off. So all you need do is take your vehicle to a repair guy who’ll hook it to a scanner; he’ll also reset the error code, which should cost $100 to $150.
In all, the best or most accurate repair deals are gotten when you take your car to your dealership or a qualified engineer for proper diagnosis and repair.
Also Read: Water Leaking From Car Air Conditioner (Causes & Solutions)
Frequently Asked Questions
Where is the brake light switch located?
It is found on top of the pedal of the brake. And to reach the switch, you’d need to take out the cover of the brake pedal.
How much does it cost to replace a brake light switch?
They’re usually not that expensive. They could be gotten from that local automobile parts store for as low as 20 dollars.
How do I know if my traction control system is working properly?
The prominent sign of a faulty TCS is slipping and sliding while driving, which is the riskiest and can result in an accident.
What should I do if my vehicle starts to slip and slide on slippery roads?
The moment you notice your vehicle begins to slide and slip on a slippery road, waste no time in submitting the car to a repairman to have him check the TCS.
How Serious Is The C1201 Code?
This hangs between serious and not serious — because it is dependent on what other problems your car might be experiencing. For example, if the problem is from a broken gas cap, it isn’t something serious because the car can function with that, though there will be noticeable lapses in its performance.
But a faulty sensor or wire is considered serious because this could cause the car to stop on the road while driving. That is why it’s important you keep a lookout for the code after activating the engine light.
How do I know if my brake light is working properly?
For the sake of certainty that your brake light is in good working condition, apply the brakes while a person stands and watches outside your car to see whether the lights are activated.
How to clear code C1201?
An OBD2 scanner is used to clear out a C1201 code. However, clearing the code and not fixing the problem are two separate things because these problems could cause permanent damage to your car if left unrepaired. So it’s best to determine its cause and get it fixed.
Can you drive with the C1201 code?
A thorough diagnosis should be made on your car to weigh the actual reasons behind the code so as to be sure if your car can hit the road with or without a C1201 code. And if the code keeps showing up while driving, it’s safe to get it fixed before driving it again.
Final Thoughts
The presence of a C1201 code Toyota means an issue with the ECS. Many things can be responsible for this, such as a faulty fuel injector or a malfunctioning TCS. So waste no time delivering your car to the mechanic if it comes up with any problem.
Changing and checking the PO error code is one good way to get the problem fixed. However, that doesn’t mean the parts that are affected wouldn’t be changed or repaired if need be.
The stability control system of Toyota gets information from ABS, declaration sensor, and yaw sensor. The motor speed sensor gives information to the Anti Lock Brake System (ABS). And these sensors are prone to experiencing faults; when they go bad, they set off a code in relation to ABS.
Meaning after verifying and getting a C1201 code, you shouldn’t bother tracking the speed wheel sensor issues. If Toyota SCS suspects wheel rocking, the vehicle will immediately swerve or skid.
When this occurs, it uses the anti-lock brake system brakes and reduces the power of the engine so as to control it.