OBD Guide

P21AE

Reductant Level Sensor C Circuit Range/Performance

P21AE is an OBD-II diagnostic trouble code meaning: Reductant Level Sensor C Circuit Range/Performance. Common causes: reductant level sensor malfunction, open or short circuit in the sensor circuit. 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
  • Reduced engine power
  • A message appears indicating that the reductant level is low
  • Increased fuel consumption
  • Problems starting the engine

Causes

  • Reductant level sensor malfunction
  • Open or short circuit in the sensor circuit
  • Poor contact in the sensor connector
  • Control unit software error
  • Sensor contamination

How to Fix

  1. Check the level of the reductant in the tank
  2. Inspect the sensor circuit for damage
  3. Check the contacts in the sensor connector
  4. Test the sensor using diagnostic equipment
  5. Replace the reductant level sensor if necessary

Related codes

Error P21AE by Vehicle Brand

FAQ

What does the P21AE code mean?

P21AE is an OBD-II diagnostic trouble code that indicates: Reductant Level Sensor C Circuit Range/Performance

What causes a P21AE error code?

The most common causes of P21AE include: Reductant level sensor malfunction; Open or short circuit in the sensor circuit; Poor contact in the sensor connector; Control unit software error.

How do I fix a P21AE diagnostic trouble code?

To fix P21AE: Check the level of the reductant in the tank. Inspect the sensor circuit for damage. Check the contacts in the sensor connector. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with P21AE?

Yes, but get it checked soon

How much does it cost to fix P21AE?

The estimated repair cost for P21AE is $28–89. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat