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Marty, Mercedes Technician
Category: Mercedes
Satisfied Customers: 53677
Experience:  Bosch Certified Master Tech. Over 35 years experience.
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Got this code after diagnostic test: "G3/4 (right O2 sensor,

Customer Question

Got this code after diagnostic test:
"G3/4 (right O2 sensor, before TWC [KAT]) : Open circuit (PO134)"
On my W220, S500 2001 merzedes Benz
Does this mean that the sensor should be replaced?
Submitted: 6 months ago.
Category: Mercedes
Expert:  Marty replied 6 months ago.

Hi, my name is***** sounds like the fault code was read with a generic scan tool. A P0134 is not a Mercedes code for this model. Generally speaking, this codes indicates either a dead sensor or a fault with the wiring to the sensor. Most of the time the fault is cured by replacing the sensor.

Let me know if you have any questions.