OBD Guide

P2AC1

Intake Air O2 Sensor Reference Voltage Circuit Low Bank 1

P2AC1 is an OBD-II diagnostic trouble code meaning: Intake Air O2 Sensor Reference Voltage Circuit Low Bank 1. Common causes: open or short circuit in the sensor circuit, poor contact in the sensor connector. Estimated repair cost: $28–89.

Severity
⚠️ Medium
Can you drive?
Yes, but get it checked soon
Approx. repair cost
$28–89 (est.)

Symptoms

  • Check Engine light comes on
  • Increased fuel consumption
  • Reduced engine power
  • Unstable idling
  • Dips during acceleration

Causes

  • Open or short circuit in the sensor circuit
  • Poor contact in the sensor connector
  • Malfunction of the oxygen sensor itself
  • Problems with power or grounding of the circuit
  • Engine ECU malfunction

How to Fix

  1. Check the integrity of wiring and connectors
  2. Measure the resistance and voltage in the sensor circuit
  3. Check the reference voltage at the sensor
  4. Replace the oxygen sensor if necessary
  5. Check and clean contacts in connectors

Related codes

Error P2AC1 by Vehicle Brand

FAQ

What does the P2AC1 code mean?

P2AC1 is an OBD-II diagnostic trouble code that indicates: Intake Air O2 Sensor Reference Voltage Circuit Low Bank 1

What causes a P2AC1 error code?

The most common causes of P2AC1 include: Open or short circuit in the sensor circuit; Poor contact in the sensor connector; Malfunction of the oxygen sensor itself; Problems with power or grounding of the circuit.

How do I fix a P2AC1 diagnostic trouble code?

To fix P2AC1: Check the integrity of wiring and connectors. Measure the resistance and voltage in the sensor circuit. Check the reference voltage at the sensor. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with P2AC1?

Yes, but get it checked soon

How much does it cost to fix P2AC1?

The estimated repair cost for P2AC1 is $28–89. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat