AutoCodes – Generic – U1300

U1300 Code - Low Voltage On Class 2 Serial Data Circuit

Quick Answer

Modules connected to the class 2 serial data circuit monitor for serial data communications during normal vehicle operation. Common causes include Repair other code first. 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: U1300 indicates Low Voltage On Class 2 Serial Data Circuit.
Common causes: Common causes include Repair other code first.
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 15,406

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 Nov 27, 2020

Description
Possible Causes
How To Fix
Tech Notes
Cost to Diagnose
FAQs
Comments
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Code U1300 Description

Modules connected to the class 2 serial data circuit monitor for serial data communications during normal vehicle operation. Operating information and commands are exchanged among the modules. In addition to this, Node Alive messages are transmitted by each module on the class 2 serial data circuit about once every 2 seconds. When the module detects one of the following conditions on the class 2 serial data circuit for approximately 3 seconds, the setting of all other class 2 serial communication Diagnostic Trouble Code (DTC) is inhibited and a DTC will set.

OBDII Code U1300 - Low Voltage On Class 2 Serial Data Circuit - AutoCodes.com — U1300 Code - Low Voltage On Class 2 Serial Data Circuit

What does this mean?

What are the Possible Causes of the DTC U1300?

Repair other code first

How to Fix the DTC U1300?

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 does this mean?

Code Tech Notes

In most cases, the U1300 code is combined with other codes, fix other codes first.

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the U1300 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 U1300 code?

Need more information on how to fix the U1300 code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the U1300 code diagnosed by a professional: Find a repair shop in your area

Information for Specific Makes

U1300 Buick — Low Voltage On Class 2 Serial Data Circuit
U1300 Cadillac — Low Voltage On Class 2 Serial Data Circuit
U1300 Chevrolet — Low Voltage On Class 2 Serial Data Circuit
U1300 GMC — Low Voltage On Class 2 Serial Data Circuit
U1300 Infiniti — AV Communication Circuit
U1300 Nissan — AV Communication Circuit
U1300 Pontiac — Low Voltage On Class 2 Serial Data Circuit
U1300 Saturn — Low Voltage On Class 2 Serial Data Circuit

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 U1300 Code

1. What are the common symptoms of OBDII code U1300 (Low Voltage On Class 2 Serial Data Circuit)?

- Common symptoms include issues with the vehicle's communication system, such as loss of communication with various control modules, erratic behavior of electronic components, and dashboard warning lights.

2. What are some possible causes of OBDII code U1300?

- Possible causes of U1300 include a short circuit in the Class 2 serial data circuit, damaged wiring harness, faulty control module, or a weak battery causing low voltage in the system.

3. How can I diagnose the issue related to OBDII code U1300?

- Diagnosing U1300 involves using a diagnostic scanner to retrieve the trouble codes, checking the voltage levels in the Class 2 serial data circuit, inspecting wiring for damage, and testing control modules for proper functioning.

4. Can a weak battery cause OBDII code U1300 to appear?

- Yes, a weak or failing battery can cause low voltage on the Class 2 serial data circuit, triggering the U1300 code. It is recommended to test and replace the battery if necessary to resolve the issue.

5. What are some repair tips for fixing OBDII code U1300?

- Repair tips include checking and repairing any damaged wiring, replacing faulty control modules, ensuring a strong battery connection, and clearing the trouble codes after the repairs are completed.

6. Is it safe to continue driving with OBDII code U1300 present?

- It is not recommended to drive with unresolved U1300 code, as it can lead to further electrical issues and potential malfunctions in the vehicle's systems. It is best to address the problem promptly.

7. How much does it typically cost to repair OBDII code U1300?

- The cost of repairing U1300 can vary depending on the underlying cause, the need for replacement parts, and labor charges. It is advisable to consult with a professional mechanic for an accurate estimate.

8. Can OBDII code U1300 be intermittent?

- Yes, U1300 can sometimes be intermittent if the underlying issue is related to loose connections, sporadic wiring faults, or temporary voltage fluctuations. It is essential to address intermittent issues promptly to prevent further complications.

9. Will resetting the trouble codes make OBDII code U1300 disappear permanently?

- Resetting the trouble codes may temporarily clear the U1300 code, but if the underlying issue causing the low voltage on the Class 2 serial data circuit is not fixed, the code is likely to reappear. It is crucial to diagnose and repair the root cause of the problem.

10. Is OBDII code U1300 specific to a certain make or model of vehicle?

- OBDII code U1300 (Low Voltage On Class 2 Serial Data Circuit) is a generic code that can be encountered in various vehicle makes and models equipped with OBDII systems.