OBD Guide

U151C

HVAC Control Module Lost Communication With Auxiliary HVAC Control Module On LIN Bus

U151C is an OBD-II diagnostic trouble code meaning: HVAC Control Module Lost Communication With Auxiliary HVAC Control Module On LIN Bus. Common causes: optional hvac control module malfunction, main hvac control module malfunction. Estimated repair cost: $56–278.

Severity
⚠️ Medium
Can you drive?
Yes, but get it checked soon
Approx. repair cost
$56–278 (est.)

Symptoms

  • Auxiliary HVAC not working
  • No auxiliary HVAC control
  • Error message on the dashboard
  • Incorrect operation of the climate control system
  • Intermittent HVAC system operation

Causes

  • Optional HVAC control module malfunction
  • Main HVAC control module malfunction
  • Open or short circuit in LIN bus wiring
  • Problems with LIN bus connectors
  • LIN bus fault

How to Fix

  1. Check wiring and LIN bus connectors between HVAC modules
  2. Check power and grounding of HVAC modules
  3. Check LIN bus resistance
  4. Replace faulty HVAC control module
  5. Check and replace if necessary LIN bus wiring

Related codes

FAQ

What does the U151C code mean?

U151C is an OBD-II diagnostic trouble code that indicates: HVAC Control Module Lost Communication With Auxiliary HVAC Control Module On LIN Bus

What causes a U151C error code?

The most common causes of U151C include: Optional HVAC control module malfunction; Main HVAC control module malfunction; Open or short circuit in LIN bus wiring; Problems with LIN bus connectors.

How do I fix a U151C diagnostic trouble code?

To fix U151C: Check wiring and LIN bus connectors between HVAC modules. Check power and grounding of HVAC modules. Check LIN bus resistance. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with U151C?

Yes, but get it checked soon

How much does it cost to fix U151C?

The estimated repair cost for U151C is $56–278. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat