OBD codes / P0160
P0160
ModerateO2 Sensor Circuit No Activity Detected (Bank 2, Sensor 2)
Safe to drive short-term — a silent downstream sensor does not upset how the engine runs. If the car recently had exhaust or underbody work, check for an unplugged connector before spending anything. Fix it before an emissions test, since the code and the incomplete monitor will both count against you.
What this code means
No activity means the computer sees a flat, unchanging signal from the bank 2 post-catalyst sensor — not high, not low, just silent, as if nothing were connected. That distinguishes P0160 from its stuck-low and stuck-high siblings (P0157, P0158) and usually points to a dead sensor, an unplugged or broken connector, or cut wiring. A failed heater circuit can also cause it: without its heater, a downstream sensor may never get hot enough to produce a usable signal, especially on short trips — a companion heater code such as P0161 is the giveaway. This code is also a classic follow-up to recent exhaust, transmission, or driveline work, where an underbody connector gets left unplugged or a harness gets pinched.
Symptoms you might notice
- Check-engine light with normal driving behavior
- Failed emissions test or incomplete readiness monitors
- Often no other symptom at all
What it costs to fix
Typical range: $80–$450 · about ~0.3–1.5 hrs of labor
| If the cause is… | Part | Labor |
|---|---|---|
| O2 sensor (Bank 2, Sensor 2) | $30–$200 | ~0.3–1 hrs |
| Wiring or connector repair | $5–$60 | ~0.5–1.5 hrs |
| Heater fuse replacement | $5–$15 | ~0.2–0.5 hrs |
The happy ending here is a reconnected plug or a fuse — nearly free. The typical ending is a sensor replacement. Budget uncertainty comes from wiring damage, which costs more in diagnosis time than in parts.
The price swings on which cause it turns out to be — so confirm the cause before paying. Diagnose P0160 for my exact vehicle →
Frequently asked
What is the first thing to check for P0160?
The connector. No-activity codes are the most likely of all O2 codes to be a simple unplugged or damaged connection, especially if anyone has recently worked under the vehicle. After that, check the heater fuse — a cold sensor produces no signal.
How is P0160 different from P0157 or P0158?
Those codes mean the sensor is talking but stuck at one extreme — low (lean) for P0157, high (rich) for P0158. P0160 means the signal is not moving at all, which shifts suspicion toward a dead sensor, disconnected wiring, or a heater that is not warming the sensor up.
Can a blown fuse really cause P0160?
Yes. Oxygen sensors need to be hot to generate a signal, and the built-in heater gets them there. If the heater's fuse or circuit fails, the sensor can stay too cold to respond — often flagged by a heater code like P0161 alongside. A fuse is a much cheaper fix than a sensor, so check it first.
Will P0160 stop my car from passing inspection?
In OBD-tested areas, yes, twice over: the active code is a fail on its own, and without a working sensor the catalyst monitor for that bank cannot complete, which also blocks readiness. Fix it, then drive enough for the monitors to run before retesting.
Seeing P0160 on your car? Get a diagnosis specific to your exact year, make and model.
Diagnose P0160 for my vehicleRelated trouble codes
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Generic OBD-II reference. Manufacturer-specific behavior varies — confirm with a scan tool and, for safety-related codes, a professional inspection.