OBD Guide

U1555

Body Control Module Lost Communication With Left Rear Seat Heating/Venting/Cooling Switch On LIN Bus

U1555 is an OBD-II diagnostic trouble code meaning: Body Control Module Lost Communication With Left Rear Seat Heating/Venting/Cooling Switch On LIN Bus. Common causes: seat heating/ventilation switch malfunction, open or short circuit in lin circuit. Estimated repair cost: $33–167.

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

Symptoms

  • Left rear seat heating/ventilation does not work
  • Seat climate control indicator does not light up
  • Error message on display
  • Intermittent operation of the heating/ventilation function

Causes

  • Seat heating/ventilation switch malfunction
  • Open or short circuit in LIN circuit
  • Poor contact at switch or BCM connector
  • Body Control Module (BCM) Malfunction
  • Switch power problems

How to Fix

  1. Check continuity of LIN circuit between BCM and switch
  2. Inspect connectors for corrosion or damage
  3. Check power and ground of switch
  4. Replace faulty heating/ventilation switch
  5. If necessary, replace or reflash the BCM

Related codes

FAQ

What does the U1555 code mean?

U1555 is an OBD-II diagnostic trouble code that indicates: Body Control Module Lost Communication With Left Rear Seat Heating/Venting/Cooling Switch On LIN Bus

What causes a U1555 error code?

The most common causes of U1555 include: Seat heating/ventilation switch malfunction; Open or short circuit in LIN circuit; Poor contact at switch or BCM connector; Body Control Module (BCM) Malfunction.

How do I fix a U1555 diagnostic trouble code?

To fix U1555: Check continuity of LIN circuit between BCM and switch. Inspect connectors for corrosion or damage. Check power and ground of switch. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with U1555?

Yes, but get it checked soon

How much does it cost to fix U1555?

The estimated repair cost for U1555 is $33–167. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat