AutoCodes – Chevrolet – U1800 Chevrolet

U1800 Chevrolet Code - Lost Communications With Fuel Injector Control Module

Quick Answer

Modules connected to the Controller Area Network (CAN) serial data circuits monitor for serial data communications during normal vehicle operation. Common causes include Faulty Fuel Injector Control Module (FICM), Fuel Injector Control Module harness is open or shorted, Fuel Injector Control Module circuit poor electrical connection. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

What it means: U1800 Chevrolet indicates Lost Communications With Fuel Injector Control Module.
Common causes: Common causes include Faulty Fuel Injector Control Module (FICM), Fuel Injector Control Module harness is open or shorted, Fuel Injector Control Module circuit poor electrical connection.
Severity: High - diagnose this code as soon as possible.
Can I drive?: Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

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Code Popularity 2,716

How popular is this code, among other codes? Low

Repair Importance Level

Urgent (Diagnose now) (3 / 3)

Repair Difficulty Level

Advanced (Pro) (3 / 3)

What is this?

Table of contents Created and updated by William Orellana on Jun 07, 2020

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code U1800 Chevrolet Description

Modules connected to the Controller Area Network (CAN) serial data circuits monitor for serial data communications during normal vehicle operation. Operating information and commands are exchanged among the modules. The modules have prerecorded information about what messages are needed to be exchanged on the serial data circuits. The messages are supervised and also, some periodic messages are used by the receiver module as an availability indication of the transmitter module. Each message contains the identification number of the transmitter module. A module with a CAN serial data circuits malfunction or which loses power during the current ignition cycle will have a Loss of Communication Diagnostic Trouble Code (DTC) set by other modules that depend on information from that failed module. If any of the CAN circuit are shorted to battery voltage, ground, or between them no communication is possible on the CAN serial data bus, a Diagnostic Trouble Code will set.

OBDII Code U1800 Chevrolet - Lost Communications With Fuel Injector Control Module - AutoCodes.com — U1800 Chevrolet Code - Lost Communications With Fuel Injector Control Module

What does this mean?

What are the Possible Causes of the DTC U1800 Chevrolet?

Faulty Fuel Injector Control Module (FICM)
Fuel Injector Control Module harness is open or shorted
Fuel Injector Control Module circuit poor electrical connection

How to Fix the DTC U1800 Chevrolet?

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

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the U1800 Chevrolet code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.

Need more information about the U1800 Chevrolet code?

Need more information on how to fix the U1800 Chevrolet code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the U1800 Chevrolet code diagnosed by a professional: Find a repair shop in your area

About the author: William Orellana is a Master Mechanic and Mechanical Engineer with over 30 years of experience diagnosing and repairing vehicles. Learn more about his background.

Frequently Asked Questions about U1800 Chevrolet Code

1. What are the common symptoms of OBDII code U1800 (Lost Communications With Fuel Injector Control Module) in a Chevrolet?

- Common symptoms include engine misfires, rough idling, poor fuel efficiency, and potential stalling or starting issues.

2. What are the possible causes of OBDII code U1800 in a Chevrolet related to lost communications with the Fuel Injector Control Module?

- Potential causes may include a faulty fuel injector control module, damaged wiring or connectors, software issues, or a malfunctioning powertrain control module (PCM).

3. How can I diagnose OBDII code U1800 in my Chevrolet if I suspect a communication problem with the Fuel Injector Control Module?

- Diagnose the code by inspecting the wiring, connectors, and modules for any visible damage or loose connections. Use a diagnostic scanner to check for communication errors and verify the functionality of the Fuel Injector Control Module.

4. Is it safe to continue driving my Chevrolet with OBDII code U1800 present?

- It is not recommended to drive with this code active, as it can lead to potential engine performance issues and further damage if left unresolved.

5. Can a DIY enthusiast repair OBDII code U1800 in a Chevrolet themselves?

- While some may be able to address simple wiring or connector issues causing the communication error, it is advisable to seek professional help for proper diagnosis and repair of this code.

6. How much does it typically cost to repair OBDII code U1800 in a Chevrolet at a repair shop?

- The repair costs for this code can vary depending on the specific underlying issue, but it may range from $100 to $500 or more, including parts and labor.

7. Are there any preventive maintenance steps I can take to avoid encountering OBDII code U1800 in my Chevrolet?

- Regularly inspecting and maintaining the electrical system, connectors, and modules in your vehicle can help prevent communication errors like U1800 from occurring.

8. Can resetting the OBDII code U1800 in my Chevrolet temporarily resolve the issue?

- Resetting the code may temporarily clear the error, but if the underlying cause is not addressed, the code is likely to reappear once the issue resurfaces.

9. Will OBDII code U1800 cause my Chevrolet to fail an emissions test?

- Yes, this code can trigger a check engine light, which may result in a failed emissions test depending on the regulations in your area.

10. How urgent is it to address OBDII code U1800 in a Chevrolet once it appears?

- It is recommended to address this code promptly to prevent potential engine performance issues and further damage to components related to fuel injection control.