OBD Guide

P20C1

Reductant Heater C Control Circuit/Open

P20C1 is an OBD-II diagnostic trouble code meaning: Reductant Heater C Control Circuit/Open. Common causes: broken wires in the heater circuit, heater relay malfunction. Estimated repair cost: $39–167.

Severity
⚠️ Medium
Can you drive?
Yes, but get it checked soon
Approx. repair cost
$39–167 (est.)

Symptoms

  • Check Engine Light Is On
  • Reduced engine performance
  • Increased emissions of nitrogen oxides (NOx)
  • Possible problems with passing technical inspection
  • SCR system error message on dashboard

Causes

  • Broken wires in the heater circuit
  • Heater relay malfunction
  • Damage to the heating element itself
  • Connector problems or contact corrosion
  • SCR control module malfunction

How to Fix

  1. Check the integrity of the wiring and connectors of the heater circuit
  2. Check the resistance of the heating element
  3. Check the functionality of the heater relay
  4. Scan for additional SCR system trouble codes
  5. Replace faulty heating element or circuit components as necessary

Related codes

Error P20C1 by Vehicle Brand

FAQ

What does the P20C1 code mean?

P20C1 is an OBD-II diagnostic trouble code that indicates: Reductant Heater C Control Circuit/Open

What causes a P20C1 error code?

The most common causes of P20C1 include: Broken wires in the heater circuit; Heater relay malfunction; Damage to the heating element itself; Connector problems or contact corrosion.

How do I fix a P20C1 diagnostic trouble code?

To fix P20C1: Check the integrity of the wiring and connectors of the heater circuit. Check the resistance of the heating element. Check the functionality of the heater relay. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with P20C1?

Yes, but get it checked soon

How much does it cost to fix P20C1?

The estimated repair cost for P20C1 is $39–167. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat