OBD Guide

C2021

Tire 1 Air Pressure Decrease

C2021 is an OBD-II diagnostic trouble code meaning: Tire 1 Air Pressure Decrease. Common causes: tire puncture or damage, natural air leak. Estimated repair cost: $6–56.

Severity
⚠️ Medium
Can you drive?
Limited driving only, diagnose soon
Approx. repair cost
$6–56 (est.)

Symptoms

  • Tire pressure indicator lights up
  • Reduced vehicle controllability
  • Increased noise when driving

Causes

  • Tire puncture or damage
  • Natural air leak
  • Pressure sensor (TPMS) fault
  • Tire valve damage

How to Fix

  1. Check the pressure in tire 1 using a pressure gauge
  2. Inspect the tire for damage or punctures
  3. If necessary, inflate the tire to the recommended pressure.
  4. If damage is found, repair or replace the tire
  5. Check the operation of the TPMS sensor if necessary

Related codes

FAQ

What does the C2021 code mean?

C2021 is an OBD-II diagnostic trouble code that indicates: Tire 1 Air Pressure Decrease

What causes a C2021 error code?

The most common causes of C2021 include: Tire puncture or damage; Natural air leak; Pressure sensor (TPMS) fault; Tire valve damage.

How do I fix a C2021 diagnostic trouble code?

To fix C2021: Check the pressure in tire 1 using a pressure gauge. Inspect the tire for damage or punctures. If necessary, inflate the tire to the recommended pressure.. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with C2021?

Limited driving only, diagnose soon

How much does it cost to fix C2021?

The estimated repair cost for C2021 is $6–56. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat