OBD Guide

B27B1

Electric Compressor Low Voltage

B27B1 is an OBD-II diagnostic trouble code meaning: Electric Compressor Low Voltage. Common causes: damage to the wiring harness to the compressor, electric compressor malfunction. Estimated repair cost: $111–556.

Severity
🔴 High
Can you drive?
Limited driving only, diagnose soon
Approx. repair cost
$111–556 (est.)

Symptoms

  • Air conditioning/heating system failure
  • Reduced performance of the climate system
  • Dashboard warnings
  • Battery overheating (in electric vehicles)

Causes

  • Damage to the wiring harness to the compressor
  • Electric compressor malfunction
  • Relay or fuse problems
  • HVAC control module malfunction
  • Corrosion or poor contacts in connectors
  • Problems with the battery or charging system

How to Fix

  1. Check the voltage at the compressor terminals with the system on
  2. Inspect the wiring harness for damage
  3. Check the condition of fuses and relays
  4. Test the resistance of the compressor windings
  5. Check connectors for corrosion and contact quality
  6. Scan the HVAC module for additional errors

Related codes

FAQ

What does the B27B1 code mean?

B27B1 is an OBD-II diagnostic trouble code that indicates: Electric Compressor Low Voltage

What causes a B27B1 error code?

The most common causes of B27B1 include: Damage to the wiring harness to the compressor; Electric compressor malfunction; Relay or fuse problems; HVAC control module malfunction.

How do I fix a B27B1 diagnostic trouble code?

To fix B27B1: Check the voltage at the compressor terminals with the system on. Inspect the wiring harness for damage. Check the condition of fuses and relays. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with B27B1?

Limited driving only, diagnose soon

How much does it cost to fix B27B1?

The estimated repair cost for B27B1 is $111–556. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat