Live Manual
Engine Error

P0140

O2 Sensor Circuit No Activity Detected (Bank 1 Sensor 2)

Severity
Low

Symptoms

Check engine light on, failed smog check

Common Causes

  • Unplugged or damaged O2 sensor
  • Melted wiring harness on exhaust pipe
  • Failed downstream O2 sensor
  • Blown heater circuit fuse

How to Fix

  1. 1 Reconnect sensor plug
  2. 2 Repair and reroute melted wiring
  3. 3 Replace Bank 1 Sensor 2 O2 sensor
  4. 4 Replace blown fuses
Estimated Repair Cost USD
$50 $300

Wiring repair: $100; O2 sensor: $150 - $300