Parts
$30–80
P0141 — O2 Sensor Heater Circuit Malfunction — Bank 1, Sensor 2
SAFEIs it safe to drive? Safe to drive — the downstream sensor is primarily an emissions monitor, and its heater failure won't strand you or damage the engine short-term.
What P0141 means
The heater element inside the downstream O2 sensor on Bank 1 has failed or its circuit is open/shorted. The heater gets the sensor to operating temperature quickly after cold start. Without it, the sensor takes much longer to reach the ~600°F needed to produce an accurate signal.
Most likely causes (in order)
- Failed O2 sensor heater element (most common — internal failure, $30–80)
- Blown fuse for the O2 sensor heater circuit
- Open or shorted wiring between the PCM and the heater terminals
- Corroded connector at the sensor
Symptoms you might notice
- Check engine light on
- Possible cold-start emissions issues
- No other noticeable symptoms for most drivers
What to check first
Measure heater circuit resistance directly at the sensor connector — disconnect the sensor and measure across the two heater wires (not the signal wires). Most downstream sensors measure 4–20 ohms when good; an open reading means the heater is dead. Check the heater fuse in the underhood fuse box before buying a sensor.
Repair cost & difficulty
Labor
0.3–0.7 hr
Difficulty
DIY-friendly