U18B5 GMC Code - Lost Communication With Hybrid Powertrain Control Module On Chassis Expansion CAN Bus
Quick Answer
Devices connected to the Chassis high speed General Motor Local Area Network (GMLAN) serial data circuits monitor for serial data communications during normal vehicle operation. Common causes include Faulty Hybrid Powertrain Control Module, Hybrid Powertrain Control Module harness is open or shorted, Hybrid Powertrain Control 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
- U18B5 GMC indicates Lost Communication With Hybrid Powertrain Control Module On Chassis Expansion CAN Bus.
- Common causes
- Common causes include Faulty Hybrid Powertrain Control Module, Hybrid Powertrain Control Module harness is open or shorted, Hybrid Powertrain Control 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.
Code U18B5 GMC Description
The Motor Control Modules and the Hybrid Powertrain Control Module 1 are all internal to the Power Inverter Module. Communication diagnostics for the serial data, including device power and ground as well as the wakeup circuits for Motor Control Modules and the Hybrid Powertrain Control Module 1 are all diagnosed from external sources only to the Power Inverter Module connector because any circuit fault condition within the Power Inverter Module will cause a complete replacement.The Diagnostic Trouble Code (DTC) will set a supervised periodic message that includes the transmitter device availability that has not been received.
What are the Possible Causes of the DTC U18B5 GMC?
- Faulty Hybrid Powertrain Control Module
- Hybrid Powertrain Control Module harness is open or shorted
- Hybrid Powertrain Control Module circuit poor electrical connection
How to Fix the DTC U18B5 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 U18B5 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.
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Frequently Asked Questions about U18B5 GMC Code
1. What are common symptoms of OBDII code U18B5 GMC?
- Common symptoms include the hybrid powertrain system malfunctioning, the vehicle going into limp mode, and the check engine light illuminating.
2. What can cause the OBDII code U18B5 GMC to trigger?
- This code is typically triggered by a communication breakdown between the hybrid powertrain control module and the chassis expansion CAN bus.
3. How serious is the U18B5 GMC code?
- This code can affect the performance and drivability of the vehicle, so it is important to address it promptly to prevent further issues.
4. How can I diagnose the U18B5 GMC code?
- Diagnosing this code usually involves using a professional OBDII scanner to check for communication errors between the control modules in the vehicle.
5. What are some repair tips for fixing the U18B5 GMC code?
- Repair tips may include checking and repairing any damaged wiring or connectors related to the hybrid powertrain control module and the chassis expansion CAN bus.
6. Can I drive my vehicle with the U18B5 GMC code present?
- It is not recommended to drive the vehicle with this code present, as it can lead to more serious issues and potential safety hazards.
7. How much does it cost to repair the U18B5 GMC code?
- The cost of repair can vary depending on the underlying cause of the communication issue, but it may involve labor costs for diagnosis and potential parts replacement.
8. Is the U18B5 GMC code specific to GMC vehicles only?
- While this code is specific to GMC vehicles, similar communication error codes may exist for other vehicle makes and models.
9. Can a DIY enthusiast fix the U18B5 GMC code?
- Depending on the individual's skill level and access to tools, a DIY enthusiast may be able to address this code by following repair guides and utilizing the necessary equipment.
10. How can I prevent the U18B5 GMC code from reoccurring?
- Regular maintenance, such as checking and maintaining the vehicle's electrical connections and system components, can help prevent the U18B5 code from reoccurring.
Discuss the causes and fixes for U18B5 GMC OBDII Code
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