Engine-Codes - Gmc - U18A4 GMC

U18A4 GMC - Lost Communication With Hybrid/EV Battery DC Charging Communications Gateway Module On High Voltage Energy Management CAN Bus

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

U18A4 GMC Possible Causes

  • Faulty Hybrid/EV Battery DC Charging Communications Gateway Module
  • Hybrid/EV Battery DC Charging Communications Gateway Module harness is open or shorted
  • Hybrid/EV Battery DC Charging Communications Gateway Module circuit poor electrical connection

How is the U18A4 GMC 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 U18A4 GMC code

Labor: 1.0

The cost to diagnose the U18A4 GMC 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)

U18A4 GMC Meaning

Devices connected to the serial data circuits monitor for serial data communications during normal vehicle operation. Operating information and commands are exchanged among the devices. The devices have prerecorded information about what messages are needed to be exchanged on the serial data circuits, for each virtual network. The messages are supervised and also, some periodic messages are used by the receiver device as an availability indication of the transmitter device. Each message contains the identification number of the transmitter device. The Diagnostic Trouble Code (DTC) will set a supervised periodic message that includes the transmitter device availability that has not been received.

More Information

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