SAE J2012 / ISO 15031-6 · powertrain

P0135: Circuito do aquecedor da sonda lambda (Banco 1 Sensor 1)

Circuito do aquecedor da sonda lambda (Banco 1 Sensor 1): Current draw or resistance of the upstream air/fuel ratio sensor heater element is out of specification.

P0135 — Diagnostic Summary
Trouble Code (DTC)P0135
Official SAE DefinitionCircuito do aquecedor da sonda lambda (Banco 1 Sensor 1)
Vehicle Subsystempowertrain
Driving SeverityMEDIUM

Observable Symptoms

  • Check Engine Light on immediately after start
  • Delayed closed-loop fuel control during warm-up

Most Probable Root Causes

  • Open heater element inside Bank 1 Sensor 1 O2 sensor
  • Blown O2 heater fuse
  • Damaged sensor wiring touching hot exhaust manifold

Step-by-Step Diagnostic Procedure

  1. Check O2 heater supply fuse for +12 V with ignition on
  2. Measure heater pin resistance across O2 sensor connector (typically 2–14 Ω)