Emission codes
P0141: oxygen sensor heater circuit (bank 1 sensor 2)
The oxygen sensor behind the catalytic converter needs its heater just like the front one. P0141 means the computer has found a fault in that heater circuit, so the converter check may not run.
P0141: can I drive, and what will the labor cost?
Estimated labor, replace downstream oxygen sensor (bank 1 sensor 2)
$33 to $110
| Labor time (estimate) | 0.3 to 1 h |
| Rate used | $110/h |
| Technician wage, United States (average) | $27.13/h |
| Low: fix when convenient Safe to drive; this sensor checks the catalytic converter, so the main effect is on emissions monitoring. | |
Labor only: parts and the diagnostic fee are not included. Hours are our estimate for a typical car; book times vary by model. Wage: BLS, May 2025.
P0141 is the generic OBD-II code for "O2 sensor heater circuit, bank 1 sensor 2". Sensor 2 sits behind the catalytic converter. It does not steer the fuel mixture on most cars; its job is to watch how much oxygen the converter stores and releases, which is how the computer decides whether the converter still works. The sensor's built-in heater lets it read soon after a start. P0141 is set when the heater current is missing, too high or out of range. The most frequent cause is the heater element failing inside the sensor. Because this sensor sits further back, under the car, its wiring is more exposed to road debris, rust and heat from the exhaust, so chafed wires and corroded connectors are more common than at the front. A shared fuse is another candidate. It is safe to drive, but the converter monitor cannot complete, so the car will not pass an OBD inspection until it is fixed.
After the repair: when does the light go off?
Light off by itself after about
2 days
| Fault-free trips needed | 3 |
| Warm-up cycles before the code can be erased | 40 |
| Stored code gone after about | 40 days |
Federal rule for model years up to 2016 (40 CFR 86.1806-05); a misfire or fuel fault must also stay away under similar conditions. Clearing codes with a scanner also resets the readiness monitors an inspection checks.
Codes, rules and labor data checked by Radif Partners · Editorial policy · Method and sources
P0141 at a glance
| Code | P0141 |
| Standard description | O2 Sensor Heater Circuit (Bank 1 Sensor 2) |
| System | Oxygen sensors |
| Severity | Low: fix when convenient |
| Common symptoms | usually none, catalyst monitor not ready for inspection |
Where the downstream sensor lives
It is threaded into the exhaust pipe just behind the converter, often near the transmission tunnel, with its connector clipped to the body or a bracket above. Wiring that hangs loose after earlier work rubs on the pipe, and salt corrodes the pins. Before ordering a sensor, follow the harness and check that the connector is clean, fully latched and not melted.
How it connects to P0420
The computer compares the upstream and downstream signals to judge the converter. Without a working downstream sensor, that judgment is not possible. If you also have P0420, fix P0141 first and drive a few days: a cold or faulty sensor 2 can make a healthy converter look worn, and the converter code sometimes goes away with the sensor.
Readiness and inspections
States that test cars with the OBD port check both the light and the readiness monitors. The California Air Resources Board fact sheet explains that a car with incomplete monitors fails until it has been driven enough for them to run, typically about a week of mixed driving. After the repair, plan that time before an inspection. Compare with P0135, the same fault at the front sensor.
Likely causes of P0141, in order
| Cause | How often |
|---|---|
| Heater element open inside the downstream sensor | most frequent |
| Wiring chafed against the exhaust or underbody | frequent |
| Blown heater fuse | frequent |
| Corroded connector | less frequent |
P0141 repairs and labor time
| Repair | Labor (estimate) | At $110/h |
|---|---|---|
| Replace downstream oxygen sensor (bank 1 sensor 2) | 0.3 to 1 h | $33 to $110 |
| Repair heater wiring or connector | 0.5 to 1.5 h | $55 to $165 |