AutoCodes – GMC – B1103 GMC

B1103 GMC Code - Communication Voltage Too Low

Quick Answer

When the ignition switch is turned to ON, the Sensing and Diagnostic Module (SDM) will perform turn-on test to diagnose critical malfunctions within SDM itself. Common causes include Faulty Sensing and Diagnostic Module (SDM), Sensing and Diagnostic Module harness is open or shorted, Sensing and Diagnostic 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: B1103 GMC indicates Communication Voltage Too Low.
Common causes: Common causes include Faulty Sensing and Diagnostic Module (SDM), Sensing and Diagnostic Module harness is open or shorted, Sensing and Diagnostic 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 796

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 Mar 22, 2022

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code B1103 GMC Description

When the ignition switch is turned to ON, the Sensing and Diagnostic Module (SDM) will perform turn-on test to diagnose critical malfunctions within SDM itself.
Upon passing these test ignition and deployment loop voltages are measured to ensure that they are within their normal voltage ranges. The SDM monitors the voltages at the driver low and the passenger low to detect shorts to ground or voltage in the deploy loops.
The SDM checks the wiring connection to each inflator by letting the infinitesimal current flow through the internal circuit and verify the resistance. But if the voltage is out of range, SDM is unable to check the airbag system properly.

OBDII Code B1103 GMC - Communication Voltage Too Low - AutoCodes.com — B1103 GMC Code - Communication Voltage Too Low

What does this mean?

What are the Possible Causes of the DTC B1103 GMC?

Faulty Sensing and Diagnostic Module (SDM)
Sensing and Diagnostic Module harness is open or shorted
Sensing and Diagnostic Module circuit poor electrical connection

How to Fix the DTC B1103 GMC?

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 B1103 GMC 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 B1103 GMC code?

Need more information on how to fix the B1103 GMC code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the B1103 GMC code diagnosed by a professional: Find a repair shop in your area

Precautions for SRS “AIR BAG” and “SEAT BELT PRE-TENSIONER” Service

Never probe the electrical connectors on air bag, side air curtain modules or seat belts.
Never disassemble or tamper with safety belt buckle/retractor pretensioners, adaptive load limiting retractors, safety belt inflators, or probe the electrical connectors.
Do not use electrical test equipment to check SRS circuits unless instructed to in this Service Manual.
Before servicing the SRS, turn ignition switch OFF, disconnect both battery cables and wait at least 3 minutes. For approximately 3 minutes after the cables are removed, it is still possible for the air bag and seat belt pre-tensioner to deploy. Therefore, do not work on any SRS connectors or wires until at least 3 minutes have passed.

Failure to follow this instruction may result in the accidental deployment of these modules, which increases the risk of serious personal injury or death.

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 B1103 GMC Code

1. What are the common symptoms of OBDII code B1103 GMC (Communication Voltage Too Low)?

The common symptoms of code B1103 include intermittent or complete loss of communication with various modules in the vehicle, illuminated warning lights on the dashboard, and issues with the functionality of electronic components.

2. What are the possible causes of OBDII code B1103 GMC?

The code B1103 can be caused by a faulty communication bus, damaged wiring harnesses, loose connections, or a malfunctioning control module within the vehicle's communication network.

3. How can I diagnose the cause of OBDII code B1103 GMC?

To diagnose the cause of code B1103, a comprehensive scan tool is required to communicate with the affected modules and pinpoint the location of the communication voltage issue. Checking the wiring harnesses and connectors for damage or corrosion is also recommended.

4. What are some repair tips for resolving OBDII code B1103 GMC?

Repairing code B1103 may involve repairing or replacing damaged wiring harnesses, ensuring all connections are secure, and resetting the affected control modules. Professional diagnosis and repair by a qualified technician may be necessary for complex cases.

5. Can OBDII code B1103 GMC be fixed at home?

Simple cases of code B1103, such as loose connections or minor wiring issues, may be resolved at home with basic tools and automotive knowledge. However, complex cases involving control module malfunctions may require professional diagnosis and repair.

6. Is it safe to continue driving with OBDII code B1103 GMC active?

It is not recommended to continue driving with code B1103 active, as it may lead to further communication issues within the vehicle's systems. It is advisable to address the underlying cause of the code promptly to prevent potential safety hazards.

7. How much does it typically cost to repair OBDII code B1103 GMC?

The cost of repairing code B1103 can vary depending on the underlying cause, the extent of the damage, and the labor rates of the repair facility. It is advisable to obtain quotes from multiple sources for an accurate estimate.

8. Can a low battery voltage trigger OBDII code B1103 GMC?

Low battery voltage can potentially contribute to communication voltage issues and trigger code B1103. Ensuring the vehicle's battery is in good condition and properly charged is essential for maintaining stable communication within the vehicle's network.

9. Are there any preventive measures to avoid OBDII code B1103 GMC in the future?

Regularly inspecting the wiring harnesses and connectors for signs of wear, maintaining the vehicle's battery health, and promptly addressing any communication issues can help prevent the recurrence of code B1103 in the future.

10. How long does it typically take to repair OBDII code B1103 GMC?

The repair time for code B1103 can vary depending on the complexity of the issue and the availability of parts. Simple fixes may be completed within a few hours, while more involved repairs may take longer, potentially spanning multiple days.