Error codes for Mercedes

Modern cars, “stuffed” with all sorts of bells and whistles and other devices, allow you to quickly detect a malfunction in case of timely diagnosis. Any malfunction of the car is characterized by a certain error code, which must not only be read, but also decoded. In the article we will tell you how diagnostics are carried out and how Mercedes error codes are deciphered.

Car diagnostics

To check the condition of the car, it is not necessary to go to the service station and order an expensive operation from the masters. You can do it yourself. It is enough to buy a tester and connect it to the diagnostic connector. In particular, a tester from the K line, which is sold in car dealerships, is suitable for a Mercedes car. The Orion adapter is also good at reading errors."

Mercedes G-class car

You also need to find out what diagnostic connector the machine is equipped with. If you have a standard OBD tester to determine the error codes and the car has a round test connector, you need to buy an adapter. Marked as "OBD-2 MB38pin". If you are the owner of a Gelendvagen, a 16-pin rectangular diagnostic connector will be installed on it. Then you need to buy an adapter with so-called bananas.

Many Mercedes owners have encountered the fact that some testers do not work when connected to a BC. One of them is ELM327. And so, in principle, most USB testers work. The VAG USB KKL model is one of the most economical and reliable. If you decide to buy a tester, consider this option. As for the diagnostic utility, we recommend using HFM Scan. This utility is the easiest to use. It is fully compatible with the latest tester model.

Blue Mercedes car

1. You need to download to the laptop and install the drivers for the tester. Sometimes the operating system automatically installs all the necessary programs, but in some cases, manual installation is required.
2. Run the utility and connect the tester to the laptop via a cable. Check if the utility sees the adapter.
3. Find the diagnostic port of the car and connect the tester to it.
4. You will need to turn on the ignition, but you do not need to start the engine. Run the utility and then select the port of your tester (usually there is an FTDI field in the list of ports, click on it).
5. Click the "Connect" or "Connect" button. So the utility will connect to the on-board computer and display information about it.
6. To start diagnosing a car, go to the "Errors" tab and click the "Check" button. Thus, the utility will start testing your on-board computer for faults, and then display error information on the screen.

Diagnostic socket for Mercedes cars

Decoding codes for all cars

Mercedes fault combinations include a five-digit combination of characters. First comes a letter and then four numbers. Before proceeding with the decoding, we invite you to find out what these symbols mean:

• P - means that the error received is related to the operation of the engine or transmission system.
• B - the combination is related to the operation of body systems, that is, central locking, airbags, seat adjustment devices, etc.
• C - means a malfunction in the suspension system.
• U - failure of electronic components.

The second position is a number between 0 and 3. 0 is the generic OBD code, 1 or 2 is the manufacturer's number, and 3 is the spare character.

The third position directly indicates the type of failure. May be:

• 1 - failure of the fuel system;
• 2 - ignition failure;
• 3 - auxiliary control;
• 4 - certain malfunctions at idle;
• 5 - errors in the operation of the engine control unit or its wiring;
• 6 - transmission malfunctions.

The fourth and fifth characters in a row indicate the sequence number of the fault.

Below is a breakdown of the failure codes received.

Engine errors

Below are the most common defects that can occur in the operation of Mercedes. Codes P0016, P0172, P0410, P2005, P200A - A description of these and other faults is given in the table.

Diagnostics of Mercedes cars

Combination	Description
P0016	Code P0016 means the position of the crankshaft pulley is incorrect. If the combination P0016 appears, it may be a control device, so you need to check it first. P0016 can also mean a wiring problem.
P0172	Code P0172 is common. Code P0172 means that the level of the fuel mixture in the cylinders is too high. If P0172 appears, further engine tuning needs to be done.
R2001	Fixed a malfunction in the exhaust system. Informs about incorrect operation of system channels. It is necessary to check whether the nozzles are tightened or clogged. Clean it if necessary. The problem may be the wiring, the need to adjust the nozzles, the valve breakage.
R2003	The control unit has registered a malfunction in the charge air flow system. You need to look for a wiring problem. It may also be the inoperability of the air supply valve.
R2004	The air flow temperature regulator behind the compressor is not working properly. In particular, we are talking about the left device.
R2005	The coolant level and temperature control regulator is not working or is not working properly. This error is often found on Mercedes Sprinter and Actros models. Check the electrical circuit, there may be a short circuit or broken sensor cables.
R2006	It is necessary to replace the correct regulator to control the temperature of the air flow after the compressor.
R2007	Manifold pressure sensor malfunction. There is a possibility that the problem is in the wiring.
R2008	The error code refers to the first bank heated oxygen device. You need to replace the sensor or conduct a detailed diagnosis of it, as well as check the circuit.
P0410	Intake manifold defects have been corrected.
R2009	The same problem, only concerns the second sensor of the first can.
P200A	The control unit signals the driver about a malfunction of the detonation system. Perhaps there was a malfunction of the system unit itself, or maybe this is due to a violation of the wiring, that is, its breakage. Also, it will not be superfluous to check the operation of the fuse directly on the block.
P200B	Therefore, the ECU indicates that the catalytic converter is not working properly. Its performance is lower than declared by the manufacturer. Perhaps the problem should be sought in the second heating of the oxygen sensor or in the operation of the catalyst itself.
R200C	Incorrect operating range of the first bank oxygen regulator. It makes sense to check the circuit.
R2010	The second heated oxygen sensor is not working properly. The problem lies in the electrical circuit, so you have to call to finally understand the error.
R2011	The first row knock control regulator should be checked. On cars of the Aktros and Sprinter models, such a misfortune often happens. Perhaps it's again in the damage to the circuit itself. Therefore, you need to check the wiring at the connection to the regulator. There is a high probability that the contact just left and you need to reconnect.
R2012	Damage to the electromagnetic device of the fuel vapor battery is reported. Difficulties in operation may be associated with the failure of the gas tank ventilation valve. Here you need to check the wiring in detail.
R2013	In this way, the computer informs the driver about a malfunction in the gasoline vapor detection system. This may indicate a bad injector connection, so a leak may have occurred. Also, the cause may be poor sealing of the intake system or the filler neck of the gas tank. If everything is fine with this, then this error code may be the result of a malfunctioning fuel vapor accumulator valve.
R2014	The control unit has detected a fuel vapor leak from the system. This may be the result of poor system tightness.
P2016 - P2018	The injection system reports a high or low fuel mixture. This may be due to the fact that the regulator cannot control the flow rate of the air mixture. It is necessary to conduct an exhaustive diagnosis of its operation. Perhaps the wiring contact is loose or the regulator is broken.
R2019	Very high coolant temperature in the cooling system. In the event of such an error, the on-board computer prompts the car owner to activate the emergency mode. If the coolant in the expansion tank does not boil to operating temperature, then the problem may be an open or short circuit in the sensor-ECU section. The functionality of the device must be carefully checked, as it may need to be replaced.
R201A	Malfunction of the camshaft pulley position regulator. For owners of Mercedes, Sprinter or Actros models, this error code may be familiar to you. This defect is associated with poor installation of the regulator. Perhaps a gap formed at the place of its installation, which affected the operation of the device, or there were certain problems with the wiring.
R201B	Fixed malfunctions in the onboard voltage system. Perhaps the defect is due to poor wiring or loose contact of one of the main sensors. In addition, interruptions may be related to the performance of the generator.
P201D, P201É, P201F, P2020, P2021, P2022	Thus, the driver is notified about the unstable operation of one of the six engine injectors (1,2,3,4,5 or 6). The essence of the malfunction may lie in a bad electrical circuit that needs to be ringed, or in a malfunction of the injector itself. It is necessary to carry out detailed wiring tests, as well as check the connection of the contacts.
R2023	The on-board computer indicates malfunctions that have appeared in the operation of the exhaust air supply system. First of all, you need to check the condition of the fuse box relay. Also, the malfunction may lie in the inoperative valve of the air supply system at the outlet.

Car Mercedes Gelendvagen

Your attention is presented to a small part of all the codes that may appear when diagnosing a car. Especially for users of the resource, our specialists have selected the most common combinations in diagnostics.

These errors can affect the operation of the engine, so they are important.

How to reset?

There are several ways to reset the error counter. First of all, this can be done using the software that we wrote about at the beginning of the article. In the utility window there is a button "Reset counter". The second way is described below:

1. Start the engine of your Mercedes.
2. In the diagnostic connector, it is necessary to close the first and sixth contacts with a wire. This must be done within 3 seconds, but no more than four.
3. After that, wait a three second pause.
4. And once again close the same contacts, but for at least 6 seconds.
5. This will clear the error code.

If neither the first nor the second method helped, you can use the "grandfather" method. Just open the hood and reset the negative battery terminal. Wait five seconds and reconnect. The error code will be cleared from memory.

Video "Another way to reset the error"