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AutoCodes - Generic - U1818

U1818 Code - Lost Communication With Engine Control Module On Powertrain Expansion Communication Bus

- Code Popularity: 1,973 Views
- Repair Importance Level: 3/3
- Repair Difficulty Level: 3/3
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By AutoCodes.com - Updated Jun 07, 2020
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|Code U1818 Possible Causes

  • Faulty Engine Control Module (ECM)
  • Engine Control Module harness is open or shorted
  • Engine Control Module circuit poor electrical connection
  • Faulty Hybrid/EV Powertrain Control Module

|How do I Fix the Code U1818?

Check 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.

Does your Car have Safety Recalls? → Check here

|What is the Cost to Diagnose the Code U1818?

Labor: 1.0

The cost of diagnosing the U1818 code is 1.0 hour of labor. The auto repair labor rates vary by location, your vehicle's make and model, and even your engine type. Most auto repairs shops charge between $75 and $150 per hour.

|What are Code U1818 Possible Symptoms?

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

|Code U1818 Description

Devices connected to the powertrain high-speed General Motor Local Area Network (GMLAN) 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 when a supervised periodic message that includes the transmitter device availability has not been received.

OBDII Code U1818 - Lost Communication With Engine Control Module On Powertrain Expansion Communication Bus - AutoCodes.com
U1818 Code - Lost Communication With Engine Control Module On Powertrain Expansion Communication Bus

|Need More Information on the U1818 Code?

Need more information on how to fix the U1818 code? Get Access to Factory Service Manuals

|Information for Specific Makes

  • U1818 Buick Lost Communication With Engine Control Module On Powertrain Expansion Communication Bus
  • U1818 Cadillac Lost Communication With Engine Control Module On Powertrain Expansion Communication Bus
  • U1818 Chevrolet Lost Communication With Engine Control Module On Powertrain Expansion Communication Bus
  • U1818 GMC Lost Communication With Engine Control Module On Powertrain Expansion Communication Bus

|Need Help with the U1818 Code?

Get the U1818 code diagnosed by a professional: Find a repair shop in your area

|Code U1818 comments

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