AutoCodes – Pontiac – U1099 Pontiac

U1099 Pontiac Code - Loss Of Head-Up Display Communications

Quick Answer

Modules connected to the class 2 serial data circuit monitor for serial data communications during normal vehicle operation. Common causes include Faulty Head-Up Display (HUD), Head-Up Display harness is open or shorted, Head-Up Display 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: U1099 Pontiac indicates Loss Of Head-Up Display Communications.
Common causes: Common causes include Faulty Head-Up Display (HUD), Head-Up Display harness is open or shorted, Head-Up Display 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 486

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 Apr 24, 2020

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code U1099 Pontiac 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. When a module receives a message for a critical operating parameter, the module records the identification number of the module which sent the message for the state of health monitoring/node alive messages. A critical operating parameter is one which, when not received, requires that the module use a default value for that parameter. Once an identification number is learned by a module, it will monitor for that module node alive message. Each module on the class 2 serial data circuit is required to send a Node Alive message every 2 seconds. When no message is detected from a learned identification number for 5 seconds, a Diagnostic Trouble Code (DTC) U1099 is set.

OBDII Code U1099 Pontiac - Loss Of Head-Up Display Communications - AutoCodes.com — U1099 Pontiac Code - Loss Of Head-Up Display Communications

What does this mean?

What are the Possible Causes of the DTC U1099 Pontiac?

Faulty Head-Up Display (HUD)
Head-Up Display harness is open or shorted
Head-Up Display circuit poor electrical connection

How to Fix the DTC U1099 Pontiac?

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 U1099 Pontiac 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 U1099 Pontiac Code

1. What are the common symptoms of OBDII code U1099 in a Pontiac related to loss of Head-Up Display communications?

- Common symptoms include the Head-Up Display not functioning or displaying incorrect information on the Pontiac's dashboard.

2. What are some possible causes of OBDII code U1099 in a Pontiac?

- Possible causes can include a faulty Head-Up Display module, damaged wiring or connectors, or a communication error within the vehicle's network.

3. How can I diagnose the cause of OBDII code U1099 in my Pontiac?

- Diagnosing the issue may require using a diagnostic scanner to retrieve the specific error codes, checking the connections and wiring related to the Head-Up Display, and performing a communication network test.

4. Can I still drive my Pontiac if OBDII code U1099 is present?

- It is generally safe to drive the vehicle with this code, but it is recommended to have the issue diagnosed and repaired as soon as possible to ensure proper functionality of the Head-Up Display system.

5. What are some DIY repair tips for addressing OBDII code U1099 in a Pontiac?

- DIY repair tips may include checking and securing the connections and wiring related to the Head-Up Display, resetting the system, or replacing a faulty Head-Up Display module if necessary.

6. Is it recommended to seek professional help for fixing OBDII code U1099 in a Pontiac?

- Yes, it is advisable to seek help from a qualified mechanic or dealership with experience in diagnosing and repairing issues related to the Head-Up Display system to ensure proper resolution of the problem.

7. Will resetting the OBDII code U1099 in my Pontiac make the issue go away permanently?

- Resetting the code may temporarily clear the error, but if the underlying issue causing the loss of Head-Up Display communications is not addressed, the code is likely to reappear.

8. Are there any recalls or service bulletins related to OBDII code U1099 in Pontiac vehicles?

- It is recommended to check with the manufacturer or dealership for any known recalls or service bulletins specifically addressing the U1099 code and Head-Up Display communication issues in Pontiac vehicles.

9. Can extreme weather conditions or battery issues trigger OBDII code U1099 in a Pontiac?

- Yes, extreme weather conditions or battery issues can potentially affect the communication network and trigger the U1099 code related to loss of Head-Up Display communications in a Pontiac.

10. How much can I expect to pay to repair OBDII code U1099 in my Pontiac?

- The cost of repair can vary depending on the specific cause of the issue, but it is recommended to budget for diagnostic fees, parts replacement costs, and labor charges when addressing the U1099 code in a Pontiac.