OBD Guide

B1027

Diagnosis Sensor Unit

B1027 is an OBD-II diagnostic trouble code meaning: Diagnosis Sensor Unit. Common causes: malfunction of the sensor diagnostic unit, open or short circuit in wiring harness. Estimated repair cost: $56–167.

Severity
⚠️ Medium
Can you drive?
Do not drive — repair immediately
Approx. repair cost
$56–167 (est.)

Symptoms

  • Airbag light is on
  • The security system does not pass self-diagnosis
  • Error message on the dashboard

Causes

  • Malfunction of the sensor diagnostic unit
  • Open or short circuit in wiring harness
  • Poor contact in connectors
  • Contact corrosion
  • Problems with the power supply of the diagnostic unit

How to Fix

  1. Check error codes using a scanner
  2. Inspect the wiring harness and connectors for damage.
  3. Check the supply voltage of the diagnostic unit
  4. Clean connector contacts if there is corrosion.
  5. If necessary, replace the sensor diagnostic unit

Related codes

FAQ

What does the B1027 code mean?

B1027 is an OBD-II diagnostic trouble code that indicates: Diagnosis Sensor Unit

What causes a B1027 error code?

The most common causes of B1027 include: Malfunction of the sensor diagnostic unit; Open or short circuit in wiring harness; Poor contact in connectors; Contact corrosion.

How do I fix a B1027 diagnostic trouble code?

To fix B1027: Check error codes using a scanner. Inspect the wiring harness and connectors for damage.. Check the supply voltage of the diagnostic unit. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with B1027?

Do not drive — repair immediately

How much does it cost to fix B1027?

The estimated repair cost for B1027 is $56–167. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat