OBD Guide

P123A

BARO Sensor / TC/SC Boost Pressure Sensor 'A' Correlation

P123A is an OBD-II diagnostic trouble code meaning: BARO Sensor / TC/SC Boost Pressure Sensor 'A' Correlation. Common causes: atmospheric pressure sensor (baro) malfunction, problems with the boost pressure sensor (tc/sc). Estimated repair cost: $22–89.

Severity
⚠️ Medium
Can you drive?
Yes, but get it checked soon
Approx. repair cost
$22–89 (est.)

Symptoms

  • Loss of engine power
  • Uneven engine operation
  • Increased fuel consumption
  • Check Engine light comes on
  • Jerking during acceleration

Causes

  • Atmospheric pressure sensor (BARO) malfunction
  • Problems with the boost pressure sensor (TC/SC)
  • Open or short circuit in sensor wiring
  • Mechanical problems in the boost system (leaks, turbine failure)
  • Moisture getting into sensor contacts

How to Fix

  1. Check the readings of the BARO and TC/SC sensors with a scanner
  2. Inspect the wiring and sensor connectors for damage
  3. Check the charging system for air leaks
  4. If necessary, replace the faulty sensor
  5. Clear error codes and test drive

Related codes

FAQ

What does the P123A code mean?

P123A is an OBD-II diagnostic trouble code that indicates: BARO Sensor / TC/SC Boost Pressure Sensor 'A' Correlation

What causes a P123A error code?

The most common causes of P123A include: Atmospheric pressure sensor (BARO) malfunction; Problems with the boost pressure sensor (TC/SC); Open or short circuit in sensor wiring; Mechanical problems in the boost system (leaks, turbine failure).

How do I fix a P123A diagnostic trouble code?

To fix P123A: Check the readings of the BARO and TC/SC sensors with a scanner. Inspect the wiring and sensor connectors for damage. Check the charging system for air leaks. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with P123A?

Yes, but get it checked soon

How much does it cost to fix P123A?

The estimated repair cost for P123A is $22–89. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat