Back to 2005 Mazda MX-5 Miata

2005 MAZDA MX-5 MIATA

1.8L I4RWDMANUALgas
Repairs0Labor520Torque3955Fluid7DTC803Battery0Maintenance0Recalls0
P0037low severityPowertrain

HO2S Heater Control Circuit Low Bank 1 Sensor 2

on 2005 Mazda MX-5 Miata 1.8L I4 · RWD

What this code means

The voltage in the Bank 1 Sensor 2 O2 heater circuit is lower than expected.

Symptoms

  • Check Engine Light
  • Poor catalyst monitoring

Common causes

  • Short to ground
  • Faulty sensor
  • Corroded connector

Diagnostic steps

  1. Test heater voltage
  2. Check for shorts
  3. Test resistance

Repair notes

Repair wiring or replace sensor.

Other Powertrain codes on this vehicle

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