Powertrain, generic · Fuel and air metering

P0141 O2 Sensor Heater Circuit Bank 1 Sensor 2

Check engine lightOn
EmissionsRelevant
Drive cycleRequired
Limp modeNo

The downstream oxygen sensor on bank 1 (sensor 2) has an electric heater so it reaches its working temperature quickly. The control module switches the heater on the ground side and checks both the driver voltage against the commanded state and the heater current. GM fails it outside 0.3–2.5 A (two trips; pure circuit faults are P0036–P0038 there); Ford uses P0141 as its general heater circuit code with a current window of roughly 0.22–0.465 A minimum to 3 A maximum depending on sensor supplier. Without heat the sensor signal is useless, so converter monitoring and trim are suspended.

Likely causes

Heater element in the sensor burnt out (replace sensor)
Heater supply (fuse, relay) or control wire open
Short in the heater (current too high)
Connector corroded, contact resistance

Symptoms

  • Check engine light on (usually after two drive cycles)
  • Catalyst monitor readiness not set
  • Follow-up codes P0140/P0136 possible

Repair estimate

DifficultyEasyDIY possible
Parts and labour€50–250
Time0.3–1.5 h

Typical range across vehicles; the real cost depends on what the testing finds.

What to check first

  1. Check fuse
  2. Measure heater resistance
  3. Inspect wiring

Parts involved

oxygen sensor heater bank1 sensor2oxygen sensor heater circuitfuses

Related codes

P0036P0037P0038P0054P0161P0147

References: law.cornell.edu, gsi.ext.gm.com, saabwisonline.com, newtonnet.co.uk.