Engine-Codes - Generic - U1509

U1509 - HVAC Controls Info Display Module Lost Communication With HVAC Control Module On LIN Bus

Repair Importance Level: 3/3
Repair Difficulty Level: 3/3  What is this?
Table of contents

U1509 Possible Causes

  • Faulty Heating, Ventilation, and Air Conditioning (HVAC) Control Module
  • HVAC Control Module harness is open or shorted
  • HVAC Control Module circuit poor electrical connection
  • Faulty HVAC Controls Info Display Module

How is the U1509 code repair?

Start by checking the "Possible Causes" listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector's pins.

What is the cost to diagnose the U1509 code

Labor: 1.0

The cost to diagnose the U1509 code is 1.0 hour of labor. The auto repair's diagnosis time and labor rates vary by location, vehicle's make and model, and even your engine type. Most auto repair shops charge between $75 and $150 per hour.
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Possible Symptoms

  • Engine Light ON (or Service Engine Soon Warning Light)

U1509 Meaning

The Local Interconnect Network (LIN) Bus consists of a single wire with a transmission rate of 10.417 Kbit/s. The serial data is transmitted over a LIN circuit between a master control module and other LIN devices within a particular subsystem. If serial data communication is lost between any of the LIN devices on the LIN bus network, the master control module will set a no communication code against the non-communicating LIN device. The Diagnostic Trouble Code (DTC) will set when a supervised periodic message to Heating, Ventilation, and Air Conditioning (HVAC) Controls Info Display Module from HVAC Control Module has not been received.

More Information

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Information for specific makes

  • U1509 BUICK HVAC Controls Info Display Module Lost Communication With HVAC Control Module On LIN Bus
  • U1509 CADILLAC HVAC Controls Info Display Module Lost Communication With HVAC Control Module On LIN Bus
  • U1509 CHEVROLET HVAC Controls Info Display Module Lost Communication With HVAC Control Module On LIN Bus
  • U1509 GMC HVAC Controls Info Display Module Lost Communication With HVAC Control Module On LIN Bus

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