OBD Guide

P21CE

Reductant Quality Module Performance

P21CE is an OBD-II diagnostic trouble code meaning: Reductant Quality Module Performance. Common causes: reductant quality module malfunction, problems with wiring to the module. Estimated repair cost: $56–167.

Severity
⚠️ Medium
Can you drive?
Yes, but get it checked soon
Approx. repair cost
$56–167 (est.)

Symptoms

  • Check Engine light comes on
  • Reduced engine power
  • Increased fuel consumption
  • SCR System Error Message
  • Unpleasant exhaust smell

Causes

  • Reductant quality module malfunction
  • Problems with wiring to the module
  • Low quality or contamination of the reductant
  • Control module software error
  • Mechanical damage to the module

How to Fix

  1. Check the quality and level of the reductant
  2. Diagnose the reductant quality module
  3. Check the integrity of wiring and connectors
  4. Replace the reductant quality module if necessary
  5. Update ECU software

Related codes

Error P21CE by Vehicle Brand

FAQ

What does the P21CE code mean?

P21CE is an OBD-II diagnostic trouble code that indicates: Reductant Quality Module Performance

What causes a P21CE error code?

The most common causes of P21CE include: Reductant quality module malfunction; Problems with wiring to the module; Low quality or contamination of the reductant; Control module software error.

How do I fix a P21CE diagnostic trouble code?

To fix P21CE: Check the quality and level of the reductant. Diagnose the reductant quality module. Check the integrity of wiring and connectors. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with P21CE?

Yes, but get it checked soon

How much does it cost to fix P21CE?

The estimated repair cost for P21CE is $56–167. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat