What are the causes of the fault code P0410 in Mercedes Benz?

This blog will explain all the causes of the fault code P0410 and answer the following questions: which models are affected by the fault code P0401? Can you drive the car with fault code P0410 present in the engine control unit? How much does it cost to fix the P0410 fault code?

What are the causes of the fault code P0410 in Mercedes Benz?

The fault code P0410 is related to the malfunction of the secondary air injection system found in Mercedes Benz cars, the causes are listed below:

  • Electric air pump
  • Air pump relay
  • Secondary air injection shut-off valve
  • Leak in the vacuum lines 

Let’s take a closer look at each of the causes and the possible remedies:

Electric air pump

It is the most integral part of the secondary air injection system. The electrical air pump runs on the 12 Volts power supply from the dedicated relay. The air pump relay is actuated by the engine control unit. The total run-on time of the electric air pump is limited to less than 40 seconds.

 The electric air pump is a suction-type pump with one inlet and one outlet, on the outlet side a Y joint divides the airflow for the left and the right cylinder bank. When the pump stops working due to an internal fault, it cannot supply air to the secondary air injection system.

If the power supply at the electrical coupler is within the specified range of 11 to 14 volts then it can be concluded that the electric pump is not working. Replacing the electric pump is easy as it is located in the front of the engine.

After the electric pump is replaced, the working of the secondary air injection system is checked for correct operation.

Air pump relay

The electric air pump has a 4-point relay that controls the actuation of the pump. Relays are used in electrical circuits to control heavy loads with small actuation signals. The electric air pump is a heavy load protected by a 40 A fuse.

If the electrical relay is stuck or not working even after the actuation circuit is okay, then the pump does not get the 12 V supply. The ground line goes into the engine wiring harness and connects to one of the ground points.

If a digital multimeter shows 12 V when it is connected across the pin 1 and 2 of the relay, it means the actuation signal is okay. Pin 3 always has a circuit 30 or battery live voltage, therefore if the voltage readings are okay it means that the relay is not working properly.

The fuse and the relay are located in the engine compartment fuse box, when the electric air pump is replaced; it is a common practice to replace the fuse and the replay along with it.

Secondary air injection shutoff valve

The outlet of the electric air pump is connected to two vacuum-actuated shutoff valves. The supply of vacuum is controlled by an electro-pneumatic solenoid. The engine control unit actuates the solenoid with the PWM signal.

The electro-pneumatic solenoid has one vacuum supply connection from the intake manifold. When it is actuated, the diaphragm of the shut-off valves is opened and air can be pumped into the exhaust system.

If the electrical solenoid a malfunction, the secondary air intake system cannot work and the fault code is stored in the engine control unit.

The only remedy is to renew the faulty secondary air injection solenoid and check the operation of the secondary air injection system. The two shutoff valves are mechanical and they operate depending on the vacuum supply.

Leaks in the vacuum lines

They are present between the intake manifold and the electro-pneumatic solenoid. On the output side, the vacuum lines have a Y joint and the vacuum supply is divided between the two shut-off valves. 

If there is a leak in the vacuum lines then the diagrams in the shutoff cannot be opened, and the complete secondary air injection system is inoperative. A close inspection of the vacuum lines must be performed in order to identify the vacuum leak.

The most common area of leakage is near the electric air pump as the vacuum lines go through a small opening between the solenoid and the intake manifold. Once the leak is located the vacuum hose is replaced and the functioning of the secondary air injection system is checked.

Which Mercedes Benz models are affected by the fault code P0401?

The Mercedes Benz models affected by the P0410 fault codes are listed below:

  • E class W211 E 280 / E 280 4MATIC (2005–2009 )
  • C class W204 C 300 / C 300 4MATIC  (2009–2011)
  • E class W212 E 300 2009-2011 
  • R class W251 (2006-2017)

All the above models are powered by the M272 V6 petrol engine. The fuel injection system in the M272 consists of a fuel injector in the intake manifold. Fuel is injected into the manifold and as the intake valves open, the air-fuel mixture is sucked into the cylinder.

Due to the port fuel injection and low compression ratio, the overall temperature of the exhaust gases increases very slowly. The displacement of the M272 is almost 3 liters and two catalytic converters must be brought to operating temperature faster after cold starting the engine.

Therefore, the secondary air injection system pumps air into the exhaust system for 40 seconds after the engine is started and ensures the catalytic converter reaches the operating temperature range. Once the warm-up phase is over, the secondary system has no use in the operation of the internal combustion engine.

Can you drive the car with fault code P0410 present in the engine control unit?

Yes, it is possible to drive the car with the fault code P 0410, the secondary air injection system is only active during the warm-up phase, once the engine is at operating temperature there is no effect on the performance and fuel efficiency. 

The check engine light comes as the fault is present in the fault memory of the engine control unit. Therefore it is recommended to fix the fault code P0410 as early as possible. 

How much does it cost to fix the P0410 fault code?

The cost to fix the P0410 fault code depends on the cause and the labor required to diagnose it. The following table shows the cost of the spare parts that may need replacement based on the diagnosis report from the authorized dealership.

Spare partPart numberPrice
Electric air pumpA000 140 37 85$970
Fuse and relayN000 000 00 76 59
A000 982 85 23
$10-25
Electrical solenoid A000 500 32 01$51
Vacuum hoseA117 997 09 82$ 5-10 

Conclusion

This blog explained the cause and the remedy for the P0410 fault code related to the secondary air injection system. The secondary air injection system is only found on old Mercedes Benz cars. The latest models are direct fuel injected and the compression pressure is also high so there is no need for a secondary air system.

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