OBD Guide

P0143

O2 Sensor Circuit Low Voltage Bank 1 Sensor 3

P0143 is an OBD-II diagnostic trouble code meaning: O2 Sensor Circuit Low Voltage Bank 1 Sensor 3. Common causes: open or short circuit in the sensor wiring harness, oxygen sensor malfunction. Estimated repair cost: $56–167.

Severity
⚠️ Medium
Can you drive?
Limited driving only, diagnose soon
Approx. repair cost
$56–167 (est.)

Symptoms

  • Increased fuel consumption
  • Unstable engine operation
  • Check Engine light comes on
  • Increased emissions of harmful substances

Causes

  • Open or short circuit in the sensor wiring harness
  • Oxygen sensor malfunction
  • Poor grounding of the sensor circuit
  • Problems with the ECU

How to Fix

  1. Check the integrity of the sensor wiring harness
  2. Check sensor connections and grounding
  3. Replace the oxygen sensor if necessary
  4. Check the operation of the computer

Related codes

Error P0143 by Vehicle Brand

FAQ

What does the P0143 code mean?

P0143 is an OBD-II diagnostic trouble code that indicates: O2 Sensor Circuit Low Voltage Bank 1 Sensor 3

What causes a P0143 error code?

The most common causes of P0143 include: Open or short circuit in the sensor wiring harness; Oxygen sensor malfunction; Poor grounding of the sensor circuit; Problems with the ECU.

How do I fix a P0143 diagnostic trouble code?

To fix P0143: Check the integrity of the sensor wiring harness. Check sensor connections and grounding. Replace the oxygen sensor if necessary. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with P0143?

Limited driving only, diagnose soon

How much does it cost to fix P0143?

The estimated repair cost for P0143 is $56–167. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat