Engine-Codes - Generic - U18B8

U18B8 - Lost Communication With Body Control Module On High Speed CAN Bus

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

U18B8 Possible Causes

  • Faulty Body Control Module (BCM)
  • Body Control Module harness is open or shorted
  • Body Control Module circuit poor electrical connection

How is the U18B8 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 U18B8 code

Labor: 1.0

The cost to diagnose the U18B8 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)

U18B8 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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Information for specific makes

  • U18B8 BUICK Lost Communication With Body Control Module On High Speed CAN Bus
  • U18B8 CADILLAC Lost Communication With Body Control Module On High Speed CAN Bus
  • U18B8 CHEVROLET Lost Communication With Body Control Module On High Speed CAN Bus
  • U18B8 GMC Lost Communication With Body Control Module On High Speed CAN Bus

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