U0074 2014 GMC Sierra Code - Control Module Communication Powertrain Expansion CAN Bus Off Malfunction
Quick Answer
The U0074 diagnostic trouble code (DTC) for a 2014 GMC Sierra relates to a malfunction in the Control Module Communication Powertrain Expansion Controller Area Network (CAN) Bus Off. Common causes include Wiring Harness Damage: Physical damage to the wiring harness connecting the control modules can disrupt communication on the CAN bus network, Loose Connections: Loose or corroded electrical connections between modules can lead to intermittent communication issues, Faulty Control Modules: A malfunction in one of the control modules connected to the Powertrain system can cause the U0074 code to trigger. 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
- U0074 2014 GMC Sierra indicates Control Module Communication Powertrain Expansion CAN Bus Off Malfunction.
- Common causes
- Common causes include Wiring Harness Damage: Physical damage to the wiring harness connecting the control modules can disrupt communication on the CAN bus network, Loose Connections: Loose or corroded electrical connections between modules can lead to intermittent communication issues, Faulty Control Modules: A malfunction in one of the control modules connected to the Powertrain system can cause the U0074 code to trigger.
- 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.
Fix Your Car Smarter
Try the New AutoCodes App!
Get complete OBDII diagnostics, repair solutions, and cost estimates, plus AI chat support on demand.
Code U0074 2014 GMC Sierra Description
The U0074 diagnostic trouble code (DTC) for a 2014 GMC Sierra relates to a malfunction in the Control Module Communication Powertrain Expansion Controller Area Network (CAN) Bus Off. In simpler terms, this code indicates that there is a communication issue between various control modules in the vehicle's Powertrain system. The Powertrain system is crucial for the operation of the engine, transmission, and other related components, making this issue significant for the vehicle's performance.
Common Causes of U0074 2014 GMC Sierra
- Wiring Harness Damage: Physical damage to the wiring harness connecting the control modules can disrupt communication on the CAN bus network.
- Loose Connections: Loose or corroded electrical connections between modules can lead to intermittent communication issues.
- Faulty Control Modules: A malfunction in one of the control modules connected to the Powertrain system can cause the U0074 code to trigger.
- Software Glitches: Software errors or bugs within the control modules' programming can interfere with data transmission on the CAN bus network.
- Electrical Interference: External factors such as electromagnetic interference or poor grounding can disrupt communication between modules.
Symptoms of U0074 2014 GMC Sierra
- Check Engine Light: The most common symptom associated with the U0074 code is the illumination of the check engine light on the vehicle's dashboard.
- Reduced Engine Performance: The vehicle may exhibit reduced power, hesitation, or rough idling due to the communication issue affecting the Powertrain system.
- Transmission Problems: Issues with shifting gears smoothly or erratic transmission behavior can be linked to the U0074 code.
- Loss of Acceleration: The vehicle may struggle to accelerate or respond sluggishly to driver inputs.
- Stalling: In severe cases, the vehicle may stall while driving or have difficulty starting.
How to Fix U0074 2014 GMC Sierra
- Diagnostics: Begin by using a diagnostic scanner to retrieve the DTCs stored in the vehicle's computer system and pinpoint the specific cause of the U0074 code.
- Check Wiring and Connections: Inspect the wiring harness for any signs of damage or wear, and ensure all electrical connections are secure and free of corrosion.
- Test Control Modules: Test each control module connected to the Powertrain system to identify any faulty units that may need to be replaced.
- Repair or Replace Components: Depending on the diagnosis, repair or replace any damaged wiring, connectors, or control modules to restore proper communication on the CAN bus network.
- Clear Codes and Test Drive: Once the repairs are completed, clear the DTCs from the vehicle's computer system and test drive the vehicle to confirm that the issue has been resolved.
Cost to Fix U0074 2014 GMC Sierra
The cost of repairing the U0074 code on a 2014 GMC Sierra can vary depending on the specific cause of the issue and the extent of repairs needed. In general, the typical repair costs for this type of communication problem can range from $200 to $800, including parts and labor. However, it's important to note that the final cost can be higher if multiple components need to be replaced or if additional diagnostic work is required.
Tech Notes for U0074 2014 GMC Sierra
- 2014-2018 Chevrolet Silverado
- 2015-2018 Chevrolet Suburban
- 2015-2018 Chevrolet Tahoe
If the Diagnostic Trouble Codes (DTC) P2635, U0074, and/or U18A2 are set, it may be found that the actual fuel pressure (low-pressure system) will be reading substantially higher than desired fuel pressure, in this case, the cause of the problem is a loss of communication between Engine Control Module (ECM) and Fuel Pump Control Module (FPCM).
- Diagnose for any communication DTCs set (U0074 would take priority over U18A2 if both set) before addressing DTC P2635.
- If DTC P2635 is not resolved by correcting the communication DTCs, only then should diagnose the DTC P2635.
- It has been found that a communication issue between the FPCM and ECM can potentially induce DTC P2635 and result in a pressure differential between actual and desired fuel system pressures.
- If the actual fuel pressure is substantially higher than desired (10 psi / 70 kPa or more), replacement of the fuel pump control module or fuel system components typically will not resolve this issue.
- If the actual fuel pressure is substantially lower than desired (10 psi / 70 kPa or more), this Factory Service Bulletin would NOT apply. It would be recommended to diagnose low actual fuel pressure.
Need more information about the U0074 2014 GMC Sierra code?
Need more information on how to fix the U0074 2014 GMC Sierra code? Get Access to Factory Service Manuals
Need Help with the Code?
Get the U0074 2014 GMC Sierra code diagnosed by a professional: Find a repair shop in your area
Frequently Asked Questions about U0074 2014 GMC Sierra Code
1. What are the common symptoms of OBDII code U0074 in a 2014 GMC Sierra?
- Common symptoms include the check engine light illuminating, difficulty starting the vehicle, reduced engine performance, and issues with various vehicle systems.
2. What can cause the U0074 code to appear in a 2014 GMC Sierra?
- The U0074 code typically appears due to a malfunction in the Control Module Communication Powertrain Expansion CAN bus. This can be caused by wiring issues, loose connections, or a faulty control module.
3. How serious is the U0074 code in a 2014 GMC Sierra?
- While the U0074 code may not immediately affect the drivability of the vehicle, ignoring it can lead to long-term issues with the powertrain and other vehicle systems. It is recommended to address this code promptly.
4. Can I continue driving my 2014 GMC Sierra with the U0074 code present?
- It is not advisable to continue driving your vehicle with the U0074 code present, as it can lead to further damage and safety concerns. It is recommended to have the issue diagnosed and repaired as soon as possible.
5. How can I diagnose the U0074 code in my 2014 GMC Sierra?
- Diagnosing the U0074 code typically involves using an OBDII scanner to retrieve the code and then inspecting the Control Module Communication Powertrain Expansion CAN bus for any wiring issues, loose connections, or faulty components.
6. What are some repair tips for fixing the U0074 code in a 2014 GMC Sierra?
- Repair tips may include checking and repairing any damaged wiring, ensuring all connections are secure, and replacing any faulty control modules related to the Powertrain Expansion CAN bus.
7. Can I reset the U0074 code in my 2014 GMC Sierra without fixing the underlying issue?
- While you can clear the code using an OBDII scanner, it is not recommended to do so without addressing the underlying issue. The code is likely to reappear until the root cause is fixed.
8. Is the repair for the U0074 code in a 2014 GMC Sierra something I can do myself?
- Depending on your automotive repair skills and access to tools, you may be able to address the U0074 code yourself by checking wiring, connections, and control modules. However, it is recommended to consult a professional if you are unsure.
9. Are there any recalls or technical service bulletins related to the U0074 code in a 2014 GMC Sierra?
- It is advisable to check with a GMC dealership or online resources for any recalls or technical service bulletins related to the U0074 code in your specific vehicle model and year.
10. How much can I expect to pay to fix the U0074 code in my 2014 GMC Sierra at a repair shop?
- The cost of repairing the U0074 code can vary depending on the root cause of the issue, the labor rates of the repair shop, and the cost of any replacement parts needed. It is recommended to obtain quotes from multiple shops for an accurate estimate.
Discuss the causes and fixes for U0074 2014 GMC Sierra OBDII Code
Code U0074 2014 GMC Sierra comments
No comments found for this page.
Fix Your Car Smarter
Try the New AutoCodes App!
Get complete OBDII diagnostics, repair solutions, and cost estimates, plus AI chat support on demand.