Owners of LADA cars with an electronic gas pedal may encounter error P0504 (mismatch of brake pedal sensors). Along with it, malfunctions in the engine may appear (stalls, speed fluctuates, does not start, etc.). Most often the cause is the brake pedal position sensor (brake light sensor or frog).
The brake pedal position sensor and brake light switch are mounted in one housing. Most often, the cause of its malfunction is a broken spring. In this case, you can repair the sensor yourself by replacing the spring with a new one. Or replace the sensor with a new one.
How to remove and install
Disconnect the negative terminal of the battery. Move the driver's seat as far back as possible, lift the steering column up, and remove the carpet. The sensor is located near the brake pedal, to remove it you need to remove the block with wires (by snapping the latches), and then:
- (Priora, Kalina, Granta, Niva 4x4) loosen the lock nut and unscrew the sensor.
- (Largus, Vesta, XRAY) turn the sensor counterclockwise 90 degrees and remove it from the bracket.
Installation of the brake pedal sensor is carried out in reverse order. Adjust it if necessary. We tighten the sensor until the pedal goes down. Then turn it out a little (counterclockwise 90 degrees) and secure with a lock nut. It should be so that when the brake pedal is released, the switch rod is completely “recessed”, and when the pedal is pressed, the rod should completely come out of the switch body. The process of removing and installing the sensor is also shown in the video:
Replacement of reverse sensor VAZ 2114
You can change the frog in two ways: climb into a hole (or drive the car onto an overpass) or do it while lying under the car. Many who have changed the rear light signal device themselves claim that it is easier in a pit, the sensor is clearly visible and does not splash with oil. There is an option, take the fourteenth one to a service center, where they can easily replace this device with a new one (and they will charge you the cost of two such sensors, if not three).
Reverse sensor VAZ 2114
When replacing the DHZ yourself, it is important not to waste time and quickly insert a new one! Otherwise, the oil will pour out of the box and leave a lot of pleasant memories on your clothes and the floor of the pit.
A simple diagram of how to change the reverse sensor on a VAZ 2114:
- Drive the car into a hole or onto an overpass and put the handbrake on.
- Remove the protection from the frog contacts and disconnect them.
- You should prepare some container in advance for the oil that will pour out of the sensor hole.
- Place the container, you can unscrew the sensor (if it does not give in, then you can unscrew it with a wrench with a 22-mm head; it also happens that the wrench does not help either, it can literally become stuck (the oil is nearby), then we take a chisel and a hammer and pray that everything went smoothly)
- They took out the non-working one, inserted a new one, and screwed it on.
- If the box crater is filled with oil, wipe it to remove excess dirt.
- We connected the contacts and returned the protection back.
- If enough oil has spilled out, add the required amount.
How to check
Turn on the ignition and press the brake pedal, the brake lights should light up. After releasing the pedal they should go out. If the lamps do not light up, check the brake pedal sensor and the voltage supply from the battery to the wiring harness block.
(Largus, Vesta, XRAY) Move the rod lock to the right position using a screwdriver. We check the brake pedal sensor using a multimeter in ohmmeter mode. Circuit 3-4 should be closed (resistance value is close to zero), and circuit 1-2 should be open (resistance should tend to infinity). After pressing the rod, circuit 3-4 should open, and circuit 1-2 should close. Before installation, move the rod to the left position.
(Priora, Kalina, Granta, Niva 4x4) Circuit 1-4 should be closed, and circuit 2-3 should be open. After pressing the rod, circuit 2-3 will close, and circuit 1-4 will open.
Thus, the cause of error P0504 may be:
- faulty sensor or its wiring
- Brake pedal sensor is not adjusted
- it is necessary to reprogram the ECM (instruction No. 46-15 for Lada Granta and Kalina 2 with automatic transmission, site users can download it)
To download files you need to log in to the site.
Brake lights don't light up
I recently noticed that my back feet are not burning. They don't burn at all. All. I started looking. The fuses are all intact. On the fuse on which the feet hang, there is also interior lighting, it is on. The headlight bulbs are intact. I dug up a frog under the brake pedal. Stripped off. I checked it with a tester and it works.
When pressed, the contacts open. I checked the voltage on the frog. There is tension. Appears at the exit. But it doesn’t come to the headlights. I dig further.
I unscrewed the plastic in the trunk, the sills in the cabin, climbed under the carpet, and traced where the scythe went. And it goes under the instrument panel and then gets lost. I didn't find the diagram. I sharpened the control needle, pierced it into the insulation - there is no voltage after the panel.
I looked at the recordings here on Drive. It turns out that the relay for monitoring the health of the lamps is somehow involved here. I'm removing the relay.
And here's the reason - it burned out. This was immediately obvious. I bought a new one for 173 rubles. I took apart the old one. Something burned inside him.
That's what a hole has melted through.
Plant technological instructions
P0504 - Brake pedal A/B switches, signal mismatch
Using the Lada Vesta as an example:
Code P0504 is entered if:
- the brake pedal limit switch signals “3-4/1-2” are mismatched for more than 200 seconds with the engine running in idle mode;
- or the number of presses on the brake pedal, determined by the signals of two limit switches “3-4/1-2”, differs by the value of the diagnostic threshold on a moving vehicle.
The malfunction indicator lights up on the 3rd trip after a permanent malfunction occurs.
Description of checks
The sequence corresponds to the numbers on the card.
- It checks whether code P0504 is active at the time of the request.
- Electrical circuits are being checked.
- Check the installation of the brake pedal switch.
Diagnostic information
The scan tool in Signal Monitor mode displays the pin status bit 3-4 (Brake Pedal Switch 1 parameter) and the pin status bit 1-2 (Brake Pedal Switch 2 parameter) of the brake pedal switch. The status of contacts “1-2” can also be monitored using the brake light lamps.
If a mismatch in the signals from the “1-4/2-3” switches is detected, the engine control system will operate in emergency mode until the end of the current trip.
After repair, start the engine, reset the codes and make sure there is no malfunction.
Using the Lada Granta/Kalina as an example:
Code P0504 is entered if:
- the brake pedal limit switch signals “1-4/2-3” are mismatched for more than 200 seconds with the engine running in idle mode;
- or the number of presses on the brake pedal, determined by the signals of two limit switches “1-4/2-3”, differs by the value of the diagnostic threshold on a moving vehicle.
The malfunction indicator lights up on the 3rd trip after a permanent malfunction occurs.
Description of checks
The sequence corresponds to the numbers on the card.
- It checks whether code P0504 is active at the time of the request.
- Electrical circuits are being checked.
- Adjust the brake pedal switch clearance.
Diagnostic information
The diagnostic device is in mode “1 - Parameters; 1 - General View” shows the status bit B_BREMS of contacts “2-3” of the brake pedal switch.
Monitor the state of contacts “1-4” using the brake light lamps.
If a mismatch in the signals from the “1-4/2-3” switches is detected, the engine control system will operate in emergency mode until the end of the current trip.
After repair, start the engine, reset the codes and make sure there is no malfunction.
By the way, the brake pedal position sensor can be repaired.
Keywords: lada xray sensors | Lada Vesta sensors | Lada Largus sensors | Lada Granta sensors | Lada Priora sensors | Lada Kalina sensors | 4x4 sensors | pedals lada xray | fret vesta pedals | fret largus pedals | fret pedals granta | Lada Priora pedals | fret Kalina pedals | 4x4 pedals | ECM Lada Vesta | ECM Lada XRAY | ECM Lada Largus | ECM Lada Granta | ECM Lada Kalina | ECM Lada Priora | ECM 4x4 | Niva sensors | Niva pedals | esud niva | AvtoVAZ order | universal article
1 0 0 0 0 1
Share on social networks:
Why the sound signal stopped working: where to look for the reason
Hi all! I can’t say that car horn malfunctions occur very often and everywhere. But we cannot exclude a situation in which the signal does not work.
Car horns are safety features. Moreover, they must be present in all vehicles and be in good condition. This will allow you to give a timely signal to other road users, inform about the approach, and prevent collisions and other dangerous situations.
But at some point it happens that the sound signal located on the steering wheel suddenly stops working. It is necessary to address the issue of diagnostics as soon as possible, since it is dangerous to continue operating the car with a non-working horn.
Principle of operation
Before driving, make sure that the vehicle is not parked on the ST. If the identifier light is on, we strongly do not recommend starting to drive.
When the ignition is turned on, all indicators on the instrument panel light up for 5 seconds. Then the signal goes out if the on-board computer does not detect a malfunction in the braking system.
If the handbrake light does not light up when you start the engine, you need to test its operation. Possible breakdowns:
Look for the reason in the wiring of the generator: 2 wires (red and brown) go to it. With the ignition on, connect the brown one to a metal surface. The battery indicator should light up brightly along with the handbrake (they are duplicated during the start, they light up through a diode). If the battery is on, but the handbrake is not, the diode is faulty.
Try our service station selection service
Creating an application is absolutely free and will take you no more than 5 minutes
The mileage of the car is 2500 km, and the check is already lighting up with alarming frequency. The pre-installed BC multitronic displays a message that error P0504 is a problem with the brake pedal sensor. I erase it so that it doesn’t become an eyesore, but nevertheless, the error pops up. What to do? How can I adjust/change this button? In the photo this bastard is indicated by a red arrow. As people write, you need to play with adjusting it, which is done with two nuts. The most common thing is that people adjust so that the sensor button barely touches the brake pedal pad. In general, let's give it a spin and see. My BC immediately starts yelling as soon as I start the car, saying there is a mistake. I'll go dig around this weekend.
I noticed that the error pops up more often when you stand on the brake with the selector “D” on. I think the problem is deeper than just adjusting the sensor.
Yesterday, April 14, 2014, I was at the dealer for maintenance. In particular, he voiced hemorrhoids with error P0504. The dealer cheerfully undertook to fix everything. But he didn’t fix it, he said that we need to order a brake sensor, they say it’s defective. I drove out of the gate and wasn’t even surprised when the CHECK light came on again. And this morning the car did not start from the remote control, the BRAKES light was displayed on the key fob, which was corrected by pressing the brake a couple of times, then the car simply did not move, became dull, twitched, but after hitting the brake pedal again, everything was corrected, but then again. In general, the morning did not go well. I freaked out, went to the store and bought this damn sensor.
Here he is, the bastard, in the photo. I went to the dealer, where they changed it for me in 25 minutes without charging a penny. On my part, the cost is 170 rubles for a purchase in a store. So far nothing lights up or jerks. I want to disassemble the removed sensor at home and see what in such a cheap and simple part for 170 rubles was ruining the life of a car worth 450,000 rubles! The truth is, I don’t know how to assemble it, the upper part is on three clips, which are very hard, I wouldn’t want to break it.
