OBD Guide

B104D

Blend Door Control Circuit Low

B104D is an OBD-II diagnostic trouble code meaning: Blend Door Control Circuit Low. Common causes: open or short circuit in control circuit, damper motor malfunction. Estimated repair cost: $56–167.

Severity
⚠️ Medium
Can you drive?
Limited driving only, diagnose soon
Approx. repair cost
$56–167 (est.)

Symptoms

  • Inability to adjust the temperature in the cabin
  • Constantly hot or cold air from the deflectors
  • Clicking or unusual sounds from the damper area

Causes

  • Open or short circuit in control circuit
  • Damper motor malfunction
  • Problems with the HVAC control unit
  • Oxidation of contacts or damage to the wiring harness

How to Fix

  1. Check the integrity of the wiring and contacts in the control circuit
  2. Test the damper motor for malfunctions
  3. Check voltage and resistance in the circuit
  4. Replace the motor or HVAC control unit if necessary.

Related codes

FAQ

What does the B104D code mean?

B104D is an OBD-II diagnostic trouble code that indicates: Blend Door Control Circuit Low

What causes a B104D error code?

The most common causes of B104D include: Open or short circuit in control circuit; Damper motor malfunction; Problems with the HVAC control unit; Oxidation of contacts or damage to the wiring harness.

How do I fix a B104D diagnostic trouble code?

To fix B104D: Check the integrity of the wiring and contacts in the control circuit. Test the damper motor for malfunctions. Check voltage and resistance in the circuit. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with B104D?

Limited driving only, diagnose soon

How much does it cost to fix B104D?

The estimated repair cost for B104D is $56–167. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat