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U1818 Cadillac Code - Lost Communication with Engine Control Module on Powertrain Expansion Communication Bus

- Code Popularity: 478 Views
- Repair Importance Level: 3/3
- Repair Difficulty Level: 3/3
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What are the Possible Causes of the DTC U1818 Cadillac?

NOTE: The causes shown may not be a complete list of all potential problems, and it is possible that there may be other causes.
  • Faulty Engine Control Module (ECM)
  • Engine Control Module harness is open or shorted
  • Engine Control Module circuit poor electrical connection
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How to Fix the DTC U1818 Cadillac?

Review the 'Possible Causes' mentioned above and visually examine the corresponding wiring harness and connectors. Ensure to check for any damaged components and inspect the connector pins for signs of being broken, bent, pushed out, or corroded.

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What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the U1818 Cadillac code, it typically requires 1.0 hour of labor. The specific diagnosis time and labor rates at auto repair shops can differ based on factors such as the location, make and model of the vehicle, and even the engine type. It is common for most auto repair shops to charge between $75 and $150 per hour.

What are Code Possible Symptoms?

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

Code U1818 Cadillac 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 be set when a supervised periodic message that includes the transmitter device availability has not been received.

OBDII Code U1818 Cadillac - Lost Communication with Engine Control Module on Powertrain Expansion Communication Bus - AutoCodes.com
U1818 Cadillac Code - Lost Communication with Engine Control Module on Powertrain Expansion Communication Bus

Need More Information on the Code?

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Code U1818 Cadillac comments

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