OBD-II diagnostic trouble code
P0134Caution
O2 Sensor Circuit No Activity Detected (Bank 1 Sensor 1)
The front bank-1 oxygen sensor's signal is completely flat, which can mean a dead sensor, a wiring fault, or an exhaust leak near the sensor letting in outside air.
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Code names are compiled from open/standardized SAE and ISO references. Explanations, symptoms, causes and fixes are original. Covers generic (P0/C0/B0/U0) codes only — manufacturer-specific codes are planned for a future update.
Frequently asked questions
Can I drive with P0134?
You can usually keep driving with P0134, but don't put it off — the underlying cause can get worse or lead to further damage the longer it goes unaddressed. Get it diagnosed as soon as you reasonably can.
How much does it cost to fix P0134?
The cost varies too much by cause and vehicle to give a single figure here — a diagnosis will narrow it down.
What causes P0134?
Reviewed by Artyom SemenovAutomotive Editor · Fact-checked by Yauheni Kapliarchuk, Editor-in-Chief