p0430
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Mercedes-Benz · SUVs
Catalyst System Efficiency Below Threshold Bank 2
Quick Answer
Error code P0430 on your Mercedes-Benz SUVs means: Catalyst System Efficiency Below Threshold Bank 2. This is usually fixable — see the step-by-step guide below.
Affected Models
Applies to all models
X243X247X254V167X167AMG GLB35 4MATIC 2024AMG GLC43 4MATIC 2024AMG GLC63 S 2024AMG GLE53 4MATIC+ 2024AMG GLE63 S 2024AMG GLS63 2024EQB 250+ 2024EQB 300 4MATIC 2024EQB 350 4MATIC 2024GLB250 2024GLB250 4MATIC 2024GLC300 2024GLC300 4MATIC 2024GLE350 4MATIC 2024GLE450 4MATIC 2024GLS450 4MATIC 2024GLS580 4MATIC 2024Maybach GLS600 2024
Likely Causes
How to Fix It
1
Check for related codes on Bank 2 including misfire and fuel trim codes
2
Analyze Bank 2 downstream O2 sensor signal pattern compared to upstream sensor
3
Inspect exhaust connections and gaskets around the Bank 2 catalytic converter
4
Test Bank 2 downstream O2 sensor for proper heater circuit and signal response
5
Replace the Bank 2 catalytic converter if catalyst efficiency is confirmed degraded
Pro Tip
This issue typically requires professional diagnosis. Attempting this fix without proper training could cause further problems.
Parts You May Need
Catalytic converter (Bank 2)
Downstream O2 sensor (Bank 2)
Exhaust gaskets
Exhaust studs and nuts
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