AutoCodes – Cadillac – U1901 Cadillac

U1901 Cadillac Code - Lost Communication With Infotainment Multifunction Switch Module

Quick Answer

Devices connected to the serial data circuits monitor for serial data communications during normal vehicle operation. Common causes include Faulty Infotainment Multifunction Switch Module, Infotainment Multifunction Switch Module harness is open or shorted, Infotainment Multifunction Switch 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: U1901 Cadillac indicates Lost Communication With Infotainment Multifunction Switch Module.
Common causes: Common causes include Faulty Infotainment Multifunction Switch Module, Infotainment Multifunction Switch Module harness is open or shorted, Infotainment Multifunction Switch 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 619

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 09, 2020

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code U1901 Cadillac Description

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.

OBDII Code U1901 Cadillac - Lost Communication With Infotainment Multifunction Switch Module - AutoCodes.com — U1901 Cadillac Code - Lost Communication With Infotainment Multifunction Switch Module

What does this mean?

What are the Possible Causes of the DTC U1901 Cadillac?

Faulty Infotainment Multifunction Switch Module
Infotainment Multifunction Switch Module harness is open or shorted
Infotainment Multifunction Switch Module circuit poor electrical connection

How to Fix the DTC U1901 Cadillac?

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 U1901 Cadillac 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.

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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 U1901 Cadillac Code

What does the OBDII code U1901 mean for a Cadillac?

The U1901 code indicates a lost communication issue with the infotainment multifunction switch module, which can affect various electronic functions in the vehicle.

What are common symptoms of the U1901 code?

Symptoms may include malfunctioning infotainment system features, difficulty in using controls on the steering wheel, or loss of audio and navigation functionalities.

What causes the U1901 code to trigger?

The code can be triggered by wiring issues, a faulty infotainment multifunction switch module, or problems with the vehicle's computer systems that affect communication.

Can I drive my Cadillac with the U1901 code?

While it may be safe to drive, you may experience issues with the infotainment system, which could be distracting. Itâ€™s advisable to have the problem diagnosed and repaired.

How can I diagnose the U1901 code?

Use an OBD-II scanner to confirm the code and check for any related codes. Inspect the wiring and connections to the infotainment multifunction switch module for damage or corrosion.

What are some common repair tips for the U1901 code?

Check and repair any damaged wiring or connectors, replace the infotainment multifunction switch module if necessary, and ensure all software and firmware are up to date.

Is the U1901 code specific to Cadillac vehicles?

While the U1901 code can appear in various makes and models, the specific symptoms and fixes may vary. It is commonly associated with Cadillac vehicles due to their specific infotainment systems.

Can a dead battery cause the U1901 code?

Yes, a dead or weak battery can cause communication issues with various modules, including the infotainment multifunction switch module, leading to the U1901 code.

How much does it typically cost to repair the U1901 code?

Repair costs can vary widely depending on the underlying issue, such as wiring repairs or module replacements, but it generally ranges from $100 to $500 or more.

Is it necessary to reset the code after repairs?

Yes, after making the necessary repairs, itâ€™s important to clear the code using an OBD-II scanner to see if the problem has been resolved and to reset the system.