U185C Buick Code - Battery Charger Control Module Lost Communication With Hybrid/EV Powertrain Control Module 2 On High Voltage Energy Management CAN Bus
Quick Answer
Devices connected to the serial data circuits monitor for serial data communications during normal vehicle operation. Common causes include Faulty Hybrid/EV Powertrain Control Module 2, Hybrid/EV Powertrain Control Module 2 harness is open or shorted, Hybrid/EV Powertrain Control Module 2 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
- U185C Buick indicates Battery Charger Control Module Lost Communication With Hybrid/EV Powertrain Control Module 2 On High Voltage Energy Management CAN Bus.
- Common causes
- Common causes include Faulty Hybrid/EV Powertrain Control Module 2, Hybrid/EV Powertrain Control Module 2 harness is open or shorted, Hybrid/EV Powertrain Control Module 2 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 U185C Buick Description
This diagnostic is used to check the loss of communication with the Hybrid/EV Powertrain Control Module 2 on high voltage energy management high-speed General Motor Local Area Network (GMLAN) bus. The Battery Energy Control Module supervises a periodic serial data message to check the communication status of the Hybrid/EV Powertrain Control Module 2. If this message is not received within 1 s, this Diagnostic Trouble Code (DTC) is set.
What are the Possible Causes of the DTC U185C Buick?
- Faulty Hybrid/EV Powertrain Control Module 2
- Hybrid/EV Powertrain Control Module 2 harness is open or shorted
- Hybrid/EV Powertrain Control Module 2 circuit poor electrical connection
How to Fix the DTC U185C Buick?
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 U185C Buick 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 U185C Buick code?
Need more information on how to fix the U185C Buick code? Get Access to Factory Service Manuals
Need Help with the Code?
Get the U185C Buick code diagnosed by a professional: Find a repair shop in your area
Frequently Asked Questions about U185C Buick Code
1. What does the OBDII code U185C mean on a Buick?
The U185C code indicates a loss of communication between the Battery Charger Control Module and the Hybrid/EV Powertrain Control Module 2 via the High Voltage Energy Management CAN Bus.
2. What are the common symptoms of the U185C code on a Buick?
Symptoms may include a check engine light or service hybrid system warning, reduced power mode, failure to charge the high-voltage battery, or the vehicle not starting.
3. What causes the U185C code to be triggered?
Common causes include wiring issues such as damaged or corroded connectors, a faulty Battery Charger Control Module, a malfunctioning Hybrid/EV Powertrain Control Module 2, or communication bus errors.
4. Can a weak 12V battery cause the U185C code on a Buick?
Yes, a weak or failing 12V auxiliary battery can lead to communication issues and may trigger the U185C code.
5. How is the U185C code diagnosed?
A mechanic will use a scan tool to check for related codes, inspect the wiring and connectors on the CAN bus, and perform specific tests on the Battery Charger Control Module and Hybrid/EV Powertrain Control Module 2.
6. Can the U185C code cause the vehicle to stop working completely?
Yes, if the communication loss prevents proper coordination between the modules, the vehicle may fail to start or enter a reduced power mode.
7. What are some repair steps for resolving the U185C code on a Buick?
Repairs may include checking and repairing damaged wiring or connectors, updating module software, or replacing a faulty Battery Charger Control Module or Hybrid/EV Powertrain Control Module 2.
8. Is it safe to drive a Buick with the U185C code active?
Driving with this code active is not recommended, as it may lead to reduced performance, improper charging, or potential damage to the hybrid system.
9. How much does it typically cost to fix the U185C code on a Buick?
Repair costs vary depending on the issue but can range from $100 for minor wiring repairs to over $1,000 if a module needs replacement.
10. Can the U185C code clear itself after a temporary issue?
The code might clear itself if the issue was a temporary communication glitch, but if the underlying problem persists, it will likely return.
Discuss the causes and fixes for U185C Buick OBDII Code
Code U185C Buick 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.
