OBD Guide

P20BC

Reductant Heater A Control Circuit High

P20BC is an OBD-II diagnostic trouble code meaning: Reductant Heater A Control Circuit High. Common causes: short circuit in the heater circuit, heating element malfunction. Estimated repair cost: $33–167.

Severity
⚠️ Medium
Can you drive?
Yes, but get it checked soon
Approx. repair cost
$33–167 (est.)

Symptoms

  • Check Engine light comes on
  • Possible reduction in engine power
  • Increased emissions of nitrogen oxides (NOx)
  • SCR system error message on dashboard
  • Problems starting in cold weather

Causes

  • Short circuit in the heater circuit
  • Heating element malfunction
  • Problems with the SCR control module
  • Broken or damaged wiring harness
  • Corrosion of contacts or connectors

How to Fix

  1. Check the integrity of the heater wiring harness
  2. Measure the resistance of the heating element
  3. Check the voltage at the heater connectors
  4. Inspect connectors for corrosion
  5. If necessary, replace the heating element or wiring harness

Related codes

Error P20BC by Vehicle Brand

FAQ

What does the P20BC code mean?

P20BC is an OBD-II diagnostic trouble code that indicates: Reductant Heater A Control Circuit High

What causes a P20BC error code?

The most common causes of P20BC include: Short circuit in the heater circuit; Heating element malfunction; Problems with the SCR control module; Broken or damaged wiring harness.

How do I fix a P20BC diagnostic trouble code?

To fix P20BC: Check the integrity of the heater wiring harness. Measure the resistance of the heating element. Check the voltage at the heater connectors. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with P20BC?

Yes, but get it checked soon

How much does it cost to fix P20BC?

The estimated repair cost for P20BC is $33–167. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat