P0037

What it means

O2 sensor heater control circuit on bank 1, sensor 2 reports low voltage. Likely shorted to ground or open in the heater control wire. The heater warms the sensor element to operating temperature (~600 °C); without it the sensor stays inactive in closed loop and the ECM cannot trim mixture.

Is it safe to drive?

The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical.

Most likely causes

• Heater wire shorted to ground

  high

  One of the most commonly reported causes for this code — check this first.

• Connector pins corroded - high contact resistance

  low

  Less common, but worth ruling out after the more likely causes.

• Harness chafing through insulation

  low

  Less common, but worth ruling out after the more likely causes.

Related help

• Full P0037 diagnosis, causes & costs
• How to read check engine light codes
• Is it safe to drive with the light on?