OBD Guide

B11D3

A/C Cooldown Test Performance Compressor Not Engaged

B11D3 is an OBD-II diagnostic trouble code meaning: A/C Cooldown Test Performance Compressor Not Engaged. Common causes: air conditioning compressor malfunction, open or short circuit in wiring harness. Estimated repair cost: $56–222.

Severity
⚠️ Medium
Can you drive?
Yes, but get it checked soon
Approx. repair cost
$56–222 (est.)

Symptoms

  • The air conditioner does not work or does not work efficiently
  • No cold air from deflectors
  • The Check Engine light may be on.

Causes

  • Air conditioning compressor malfunction
  • Open or short circuit in wiring harness
  • Low refrigerant level
  • Problems with the climate control unit
  • Compressor relay or fuse faulty

How to Fix

  1. Check the refrigerant level in the air conditioning system
  2. Diagnose the air conditioning compressor
  3. Check the integrity of the wiring harness and connections
  4. Check the operation of the compressor relays and fuses
  5. If necessary, replace the compressor or top up the system with refrigerant

Related codes

FAQ

What does the B11D3 code mean?

B11D3 is an OBD-II diagnostic trouble code that indicates: A/C Cooldown Test Performance Compressor Not Engaged

What causes a B11D3 error code?

The most common causes of B11D3 include: Air conditioning compressor malfunction; Open or short circuit in wiring harness; Low refrigerant level; Problems with the climate control unit.

How do I fix a B11D3 diagnostic trouble code?

To fix B11D3: Check the refrigerant level in the air conditioning system. Diagnose the air conditioning compressor. Check the integrity of the wiring harness and connections. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with B11D3?

Yes, but get it checked soon

How much does it cost to fix B11D3?

The estimated repair cost for B11D3 is $56–222. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat