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P0433 Mercedes-Benz Code - Heated Catalyst Efficiency Below Threshold Bank 2

- Code Popularity: 3,969 Views
- Repair Importance Level: 2/3
- Repair Difficulty Level: 2/3
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What are the Possible Causes of the DTC P0433 Mercedes-Benz?

NOTE: The causes shown may not be a complete list of all potential problems, and it is possible that there may be other causes.
  • Air leak before catalytic converter
  • Faulty oxygen sensor
  • Faulty Catalytic Converter
⚠ Does your Mercedes-Benz have Safety Recalls? → Check here

How to Fix the DTC P0433 Mercedes-Benz?

Review the 'Possible Causes' mentioned above and visually examine the corresponding wiring harness and connectors. Ensure to check for any damaged components and inspect the connector pins for signs of being broken, bent, pushed out, or corroded.

Code Tech Notes

As the code description implies the P0433 code means that the vehicle's control module has detected that the three-way catalytic converter is not working properly (is not as efficient as the factory is expecting). Replacing the oxygen (O2) sensors may sometimes fix the code, but in most cases the catalytic convert needs to be replaced to fix the problem. If the P0433 code is combined with other codes, try fixing the other codes first.

Search for P0433 Mercedes-Benz Questions and Answers: Search here →

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the P0433 Mercedes-Benz code, it typically requires 1.0 hour of labor. The specific diagnosis time and labor rates at auto repair shops can differ based on factors such as the location, make and model of the vehicle, and even the engine type. It is common for most auto repair shops to charge between $75 and $150 per hour.

What are Code Possible Symptoms?

  • Engine Light ON (or Service Engine Soon Warning Light)

Code P0433 Mercedes-Benz Description

The Engine Control Module (ECM) monitors the switching frequency ratio of heated oxygen sensors 1 (front O2 sensor) and heated oxygen sensors 2 (rear O2 sensor).
A three way catalyst converter (Manifold) with high oxygen storage capacity will indicate a low switching frequency of heated oxygen sensor 2. As oxygen storage capacity decreases, the heated oxygen sensor 2 switching frequency will increase.
When the frequency ratio of heated oxygen sensors 1 and 2 approaches a specified limit value, the three way catalyst malfunction is diagnosed.

OBDII Code P0433 Mercedes-Benz - Heated Catalyst Efficiency Below Threshold Bank 2 - AutoCodes.com
P0433 Mercedes-Benz Code - Heated Catalyst Efficiency Below Threshold Bank 2

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Code P0433 Mercedes-Benz comments

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