Engine-Codes - Chevrolet - U172A CHEVROLET

U172A CHEVROLET - Left High Beam Control Module Lost Communication With Left Headlamp Horizontal Motor

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

U172A CHEVROLET Possible Causes

  • Faulty Left Headlamp Horizontal Motor
  • Left Headlamp Horizontal Motor harness is open or shorted
  • Left Headlamp Horizontal Motor circuit poor electrical connection
  • Faulty Left High Beam Control Module

How is the U172A CHEVROLET 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 U172A CHEVROLET code

Labor: 1.0

The cost to diagnose the U172A CHEVROLET 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)


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 the Left High Beam Control Module from the Left Headlamp Horizontal Motor has not been received.

More Information

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