Let's discuss the problem of errors p0504 (misalignment of brake pedal sensors) occurring on VAZ cars: Lada Granta, Datsun On-Do, Kalina, Niva, Priora, which I personally have not encountered in my car, but I have heard about it from other motorists who decided Also change the standard brake light bulbs to LED ones.
On vehicles with an electronic gas pedal, the brake pedal position sensor and brake light switch are combined in one housing.
It is their “mismatch” that is determined by the controller, registering fault code P0504.
In many cases, this error is associated with a poorly adjusted sensor or its malfunction.
#1 Zanozza
There is a problem that ruins the life of pretty good cars from the Kalina-2 series. I have a hatch, automatic. It's a normal car, it runs well, it's quite comfortable, there are no special problems.
But there is a problem that ruins life! This is error P0504 “Mismatched signal from the brake pedal sensors.” What's happening. When you are trudging through a dense and long traffic jam, you almost always drive on the brake pedal. You won't stop, but you won't accelerate either. It is at this moment that the error pops up. AvtoVAZ fights back, saying the driving style is incorrect. Great, but this is nonsense! Why doesn’t Mitsubishi give me such an error in the same situation? Well, okay, if it would just display an error and just reset it and that’s it. But the situation tends to get worse. It is expressed in the fact that the floating contact in the sensor over time begins to hang in a closed state, to become welded, simply put, and when you release the brake pedal, the car does not respond to the gas pedal and only after slamming your foot on the brake pedal, the contact falls off and the car starts to drive. Not only do you turn into a nuisance on the road with this behavior of the car, but also a dangerous nuisance, because the car can simply jerk when the sensor is triggered. As a result, a sensor costing 170-200 rubles causes a car worth 450,000 rubles to stall.
I disassembled the sensor, I categorically did not like how it was built inside, with a crooked spring, with contacts of different sizes, with traces of burning and welding. Moreover, I disassembled the sensor that came from the factory with the car. Over the course of 9,000 km, three of them have already been replaced, and we are planning to install a fourth, because the car again began to feel dull and flash with error P0504. People are starting to put transistors into the sensor circuit in order to reduce the current and voltage, so that the contact does not become welded, and to replace the sensor with sensors from Toyota and Audi. I myself bought a sensor from Audi and will install it. But explain to me what kind of disgusting this is? More precisely, ask AvtoVAZ – what kind of disgusting thing is this? After all, the problem with the sensor is not only on my car, type the question into Google, go to drive2 and you will see that almost everyone who has a K-2, Grant, etc. suffers from this issue. Is this a design flaw, a bad supplier, etc.? It turns out I'm afraid to use the brakes on my car! Well, isn't it nonsense? What does AvtoVAZ’s answer about the wrong driving style mean? Driving on highways is easy and simple, but the car lives most of its life in the city, and the city means traffic jams! Do you have any driving style in traffic jams?
Dear Sirs of the magazine “Behind the Wheel”. Work with the manufacturer on this issue. This needs to be addressed, because a little thing is a disgrace; in essence, the car is no longer so bad!
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OBD-II Error P0504: Brake Light Switch
The Powertrain Control Module (PCM stores trouble code P0504) when it detects a malfunction in the vehicle's brake light switch. A warning light comes on on the dashboard.
When a fault occurs in the brake light circuit, a number of problems can arise. To prevent the vehicle from getting into a dangerous situation, this error will be recorded and the error warning indicator will remain on until the cause is corrected and the code is cleared from the PCM.
Reasons for the error
The causes of the P0504 code are quite simple and easy to diagnose. These include:
- faulty brake light fuse
- damaged or faulty brake light switch
- brake light lamp
- open or short circuit in the brake light wiring
- problem in the connector or circuitry of the brake switch
Symptoms of error P0504
The first sign of an error will be an illuminated “Check Engine” light. In addition, you may notice other symptoms, including:
- pressing the brake pedal does not disable the vehicle's cruise control system;
- one or both brake lights do not turn on when you press the brake pedal;
- one or both brake lights remain on even after you take your foot off the brake pedal;
- pressing the brake pedal at speed causes the engine to stop;
- On an automatic transmission, it is impossible to shift the shift lever.
Diagnosis of the error
If the error code is determined using an OBD-II scanner, it is cleared. All possible causes must be checked. From simple to more complex. You need to start with fuses and light bulbs. If the problem persists, you need to check the brake light switch, wiring, and connectors.
Common diagnostic errors
Often, when the brake light comes on, it is not the driver who assumes that the problem is a burnt out bulb. Replacing the light bulb may not solve the problem, because the source could be the wiring or switch. If the fault is in the switch, then replacing the fuse will do nothing. The new one will also burn out.
How serious is the P0504 code?
It is very dangerous when the brake lights do not work. The car driving behind you cannot correctly assess the situation and your actions, which can lead to an accident. Likewise, if pressing the brake pedal does not disengage the cruise control system, the consequences can be very dire.
What needs to be repaired for error code P0504?
In most cases, fixing the cause of the P0504 code is quite simple. Here are some of the most typical situations:
Video “Eliminating squeaks”
You can learn how to solve one of the problems associated with the clutch in a car from the video from the author Konstantin Biyanov.
Hello everyone! I would like to tell you a little about the M74 ECU and the common error “P0504 Incorrect signal from the brake pedal switches.” In connection with the transition to new toxicity standards, AVTOVAZ engineers and designers have developed a new line of M74 and M17.9.7 ECUs. The ECUs can be said to be normal, but have not yet been fully tested. After all, cars on these ECUs are very much “strangled” by toxicity standards and therefore, without reprog and installing firmware e2 or lower, you can’t drive the car in any way, but this action is not all available now, since the protocol, pads and the reprog algorithm itself have changed with the ECU, in Therefore, it is necessary to have an additional module for the programmer. Diagnostics of ECU data is already available, since all major companies have taken care of their customers and have released software updates.
Error P0504 for Lada cars
During operation of a modern car, defects in engine operation may appear: failures, short-term lack of response of the gas pedal, etc. At the same time, the “Check Engine” icon lights up on the instrument cluster panel, which translated from English sounds like “check the engine.” The car owner goes for diagnostics, where a computer connected to the car detects error P0504. The brake pedal position sensor (frog) is responsible for this failure in the system. Next, we will tell you where the sensor is installed, how to check, repair and replace it.
Summarizing
Summarizing what has been said about the possible reasons that caused the failure and error P0504, it’s time to draw up an indicative checklist according to which you should act when searching for the cause. Once you find the problem, you can reset the error.
- Adjusting the gap in the middle of the brake pedal and limit switch rod.
- Cleaning and repair, installation of a new brake pedal sensor. To do this, you need to check the return of the rod, as well as the spring stiffness. The number of the brake pedal limit switch is 2118-3720010.
- Inspect fuse F23 (the number does not always match).
- Checking and installing sensor lamps.
- Inspect and clean the connections of the rear light, pedal end switch, and so on along the chain.
- Checking or dismantling the on-board computer, as well as flashing the electrical control unit.
Car : Lada Granta. Asks : Evgeniy Denisov. The essence of the question : Lada Granta is getting error p0504?
Hello, please tell me what could be the cause of the malfunction on my Lada Granta: the check light periodically lights up, on the on-board computer and during diagnostics using ELM 327 it was possible to establish error code p0504, what does this mean and how to fix it?
Causes and symptoms of malfunction
Most often, error P0504 worries owners of Lada: Grant, Priora, Kalina and other VAZ cars with an ECU. Often a defect appears on GAZ cars, for example, GAZelle NEXT. But owners of foreign cars are less likely to contact the service to eliminate error p0504 and replace the sensor (frog). Most likely, the quality of foreign spare parts is much better. What symptoms indicate that the brake pedal sensor is faulty:
- The engine begins to work unnaturally: it feels like it either stalls while driving, then immediately starts.
- The traction disappears at around 40 km/h, but after applying the gas, the former agility is restored. Then the defect appears again.
- The brake lights do not light up, or on the contrary they work constantly.
The cause of incorrect operation of the “frog” can be: mechanical damage, oxidation of contacts or wire breakage. Sometimes a failure occurs due to the burnout of both brake light bulbs. Due to the listed defects, an error appears in the system under code p0504. It can be removed, but it will appear again soon.
Pre-installation diagnostics
Before buying a new product and installing it to replace a seemingly faulty old sensor, try diagnosing and troubleshooting it yourself. So, on the body of the product there are two special nuts, one on top, the other on the bottom. The top nut adjusts the gap of our sensor. As mentioned earlier, in some cases the gap is set incorrectly, which disrupts the normal movement of the button. Your task is to find and set the optimal gap so that nothing interferes with the operation of the button. After the adjustment work, reset the ECU error, start the car engine and let it run for 15-20 minutes (the error does not register immediately). If the error does not appear, it means that the reason for the incorrect operation of the internal combustion engine is incorrect settings of the Granta brake sensor. Otherwise, you should replace the faulty device with a new, working one.
How to change
The sensor is located slightly above the brake pedal lever. To find it, you need to look under the torpedo. On Lada Priora, Grant and Kalina, a 19 mm open-end wrench will be required for dismantling. The replacement process looks like this:
- Remove the negative terminal from the battery
- Disconnect the 2 plugs from the sensor.
- Loosen the locknut with a 19 mm wrench (remember its approximate location).
- Unscrew the sensor counterclockwise.
- Install a new one and secure it with the adjusting nut.
- Connect the battery.
- Turn on the diagnostic equipment and clear the old error P0504.
The old sensor is quite repairable. In most cases, the cause of the malfunction is a broken spring. If you disassemble the body and install a new spring, the “frog” will work again.
Car owner's comment: On my Lada Grant, a spring broke in the sensor and began to close the contacts of the limit switches. When I left the car overnight, the ignition did not seem to turn off, which is why the battery ran out completely several times. I bought a new battery, but the problem did not go away until I made diagnostics and replaced the sensor. At the same time, the Check Engine did not light up.
Brake pedal sensor Lada Kalina
Lada Priora Sedan constructor, assemble it yourself Logbook Mileage and clutch replacement
The Kalina brake pedal sensor is a technical device that is used to monitor the degree of impact on the brake pedal. Quite often, car owners of the VAZ line complain about breakdowns or incorrect adjustment settings of the product.
Fortunately, the process of adjusting or replacing a part is not very difficult if certain nuances are observed.
Performance diagnostics
Checking the functionality consists of: 1. Testing the product with a multimeter. 2. Disassembly and visual inspection of the internal components of the part.
3. Replacement sensor is not known to be good.
The first method involves alternately measuring the contacts of the dismantled sensor. The point is to check each contact individually and in pairs (second and third contact). This is quite convenient to do, since at the place where the contact chip is connected, all connectors are numbered.
The second method is used to identify faulty or deformed internal elements of the product (in most cases, damaged springs).
There should be no traces of oxidation or contamination. If there are any, clean them out.
The third method is quite simple and trivial. Install a new part to replace the one whose serviceability you doubt.
When the system is restored to normal operation, the malfunction indicator (check engine) should go out (if it does not disappear within 15 minutes, the error should be reset manually).
Signs of a faulty brake pedal sensor Lada Kalina
In order to understand that the Kalina brake pedal position sensor is the cause of the vehicle’s incorrect operation, pay attention to the following signs:
- presence of error “P-0504” on the dashboard;
- a significant decrease in power and engine responsiveness when pressing the gas pedal;
- increase in engine speed (short-term) when changing gears.
Main causes of sensor failure
In order to identify the reasons that interfere with the normal operation of the device, it is necessary to disassemble it and carry out a thorough inspection to identify deformations and damage. The following defects are most common:
- the internal (small) spring, which is located on the rod, shows signs of deformation or distortion;
- the contact terminals of the product have physical oxidation;
- backlash of the moving contact;
- Quite low quality of factory production (defective, flimsy internal elements of the device).
Adjusting the brake pedal sensor Kalina
If the sensor is in good condition, and incorrect operation of the internal combustion engine continues to bother you, try adjusting the product yourself
Please pay attention to the following features:
- The sensor must be screwed in clockwise until the brake pedal begins to move down. Then you will need to slightly unscrew the product and secure its position using the fastening nut.
- The result should be such that when there is no action on the pedal, the sensor rod is recessed into the housing, and when the pedal is applied, on the contrary, it is completely released from the housing.
- As for the working gap, it is adjusted using two nuts (one at the top, the other at the bottom). The adjustment is carried out using the upper nut, which is tightened, and the lower one, on the contrary, is unscrewed. The entire process is carried out until the button is completely recessed into the body when the brake pedal is applied. However, you should not overdo the adjustment; in other words, you should leave a small gap or travel margin (approximately 2 to 5 millimeters).
Removal and installation
Replacing the brake pedal sensor on Kalina is carried out using an adjustable wrench set to “19”. The sensor itself is located above the brake pedal under the steering column. Conventionally, the removal stages can be divided into 5 steps:
- Before starting electrical work, it is recommended to disconnect the negative wire (terminal) from the battery.
- Then you need to move into the car interior on the driver’s side. For ease of operation, it is advisable to move the driver's seat in the opposite direction from the dashboard.
- Find the location of the sensor. Find a contact chip with wires. Press and hold the 2 plastic fasteners located on both sides of the chip. Pull the connector out of the sensor connector.
- Take the wrench in your hands and loosen the fastening nut. After which the sensor can be unscrewed freely.
- The installation process is similar to the removal procedure, except that you will need to make adjustments (tuning), the process of which is described in detail in the previous section.
Which one to buy
Experts and service workshop specialists recommend purchasing an original brake sensor. It is of better quality and lasts longer.
Table 1. Price of brake pedal position sensor
| Manufacturer | Code | Cost, rub. |
| AvtoVAZ | 11183720010 | 170 |
| Avar | 2113720 | 180 |
| AMY | 11183720010 | 95 |
Before changing the “frog”, you can “ring” it with a tester to make sure the part is working.
Technical description and interpretation of error P0504
This diagnostic trouble code (DTC) is a generic powertrain code. The P0504 code is considered a common code because it applies to all makes and models of vehicles. Although the specific repair steps may vary slightly depending on the model.
Your vehicle's powertrain control module (ECU) issues a P0504 code in response to a recognized failure in the brake light circuit. The vehicle's computer monitors all circuits for abnormalities such as no voltage or out of range conditions.
The brake light switch is tied to several circuits, each of which can lead to a dangerous situation. The brake light switch itself consists of two signal outputs, and if the switch is faulty, the problem is detected and this code appears.
This is not a costly failure in terms of parts cost or labor involved in replacement. But for your safety, it is necessary to carry out repairs as soon as possible.
What to do if it is not possible to purchase a sensor
It also happens that error p0504 appears at the most inopportune moment, for example, when you are in some outback and it is not possible to purchase a new sensor.
In this case, you should remove the same sensor and try to disassemble it. It is quite possible that the contacts in it simply burned out. A breakdown of this type is not uncommon, especially on the Lada Granta.
But there is another, fairly common reason for such a breakdown. This is a spring that has become so stretched over time that it can no longer perform its intended functions. To fix this problem, simply replace the spring.
And in conclusion, I would like to note that if error p0504 appears on the on-board computer of your Lada Granda quite often, then we can say with almost 100% certainty that the brake sensor is to blame.
To eliminate a constantly recurring problem, you should simply purchase a new sensor from a specialized store. It is very noteworthy that if your car is still under warranty, you can contact an authorized dealer to fix the problem, since the problem is covered under warranty.
Symptoms of malfunction
The main driver symptom of P0504 is the MIL (Malfunction Indicator Light) illumination. It is also called Check engine or simply “check light”.
They can also appear as:
- The brake lights will either remain on continuously or not illuminate when the pedal is pressed.
- It will be difficult or impossible to move.
- The car may stall while moving if you press the brakes.
- With this problem, cruise control cannot be activated.
Reasons for the error
A P0504 code may mean that one or more of the following problems have occurred:
- Short circuit in the brake light switch signal circuit.
- There is a malfunction in the brake light switch, the failure of which is due to wear.
- There is a problem with the fuses, sometimes they fail due to moisture getting into the circuit or the brake light burning out.
- If the wiring harness, or more specifically the connectors, are loose or disconnected, it will cause a correlation problem between the switch and the ECU.
- And of course, the ECU itself could fail.
How to Troubleshoot or Reset Trouble Code P0504
Some suggested steps to troubleshoot and fix error code P0504:
- With the help of an assistant, check the brake lights. Make sure they work, turning on and off, and that the bulbs are in order.
- If the brake lights stay on continuously, the brake light switch is either not adjusting properly or is faulty. The same applies to faulty lamps. Move the driver's seat back and look under the dashboard. Squeeze the tabs on the electrical connector located on the brake light switch and remove the connector.
- Using a voltmeter, check the voltage on the red wire in the connector. Place the black wire on the ground and the red wire on the red wire terminal. The voltmeter should show a voltage of 12 volts, if not, you should check the wiring to the fuse box.
- Connect the connector to the switch and measure the white wire with the pedal pressed. You should have 12 volts with the pedal pressed and no voltage with the pedal released. If there is no voltage, replace the switch. If there is voltage on the white wire with the pedal released, also replace the switch.
- If the switch has an adjustment, check it. The switch must be in good contact with the brake pedal lever and fully depressed.
- If the brake lights are working fine but you still have a code, check the other wires at the brake light switch. Remove the connector and check the remaining wires for power. Make a note of the location of the power wires and replace the connector. Secure the rear wire next to the power wire with the pedal pressed. If there is no power, replace the switch.
- If the power was turned on when the pedal was pressed in the last test, the switch is OK. There is a problem when connecting to the control unit or with the vehicle control unit itself.
- Connect the control unit and the brake pedal sensor via ground. If the voltmeter shows 12 volts, then the control unit is faulty. If there was little or no voltage, replace or repair the harness from the control unit to the sensor.
Diagnosis and problem solving
The main problem is considered to be a discrepancy between the data in the PCM and the brake pedal sensor. Therefore, let's take a closer look and describe some suggested steps to troubleshoot and fix error code P0504.
The brake light switch is located under the instrument panel at the top of the brake pedal lever. The brake booster raises the pedal to the fully extended position. The brake light switch is mounted on a crossbar support bracket directly behind the brake pedal mounting bracket.
The only way to access the switch is to move the front seat back, lie on the backrest and look up under the dash. You will see a bracket with a switch near the top of the brake pedal lever. The switch will have four or six wires.
The switch rests on the bracket so that its drive rod is in contact with the brake pedal lever when the pedal is fully extended. At this moment, the switch is pressed on the brake pedal lever, cutting off the voltage supply.
When you press the brake pedal, the lever extends to engage the switch and turn on the brake lights. After releasing the pedal, the lever presses the bar again, turning off the brake lights.
Therefore, with a high degree of probability, we can say that replacing this sensor will eliminate problems with error P0504.
