AutoCodes – GMC – P1B18 GMC

P1B18 GMC Code - Hybrid/Electric Vehicle Battery 27 Circuit High Voltage

Quick Answer

The Hybrid/Electric Vehicle battery pack contains 288 cells. Common causes include Faulty Hybrid/Electric Vehicle Battery Pack, Faulty Hybrid/Electric Vehicle Battery Interface Control Module. 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: P1B18 GMC indicates Hybrid/Electric Vehicle Battery 27 Circuit High Voltage.
Common causes: Common causes include Faulty Hybrid/Electric Vehicle Battery Pack, Faulty Hybrid/Electric Vehicle Battery Interface Control Module.
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 816

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 Mar 08, 2020

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code P1B18 GMC Description

The Hybrid/Electric Vehicle battery pack contains 288 cells. Groups of three cells are welded together in parallel. There are a total of 96 cell groups in the hybrid/EV battery pack assembly. These cell groups are electrically connected in-series. Each individual cell group is rated at 3.7 V, for a nominal system voltage of 355 V direct current. The battery cells are also grouped together into three sections. The first 90 cells/30 cell groups make up battery section one. This section is adjacent to the cowl and contains batteries 67 through to 96. Battery section two is located behind section one. It is made up of 72 cells/24 cell groups and contains batteries 43 through to 66. The transverse battery section is section number three, it is made up of the remaining 126 cells/42 cell groups and contains batteries 1 through to 42. The three battery sections are individually serviceable components.
The battery energy control module monitors the voltage of the 96 battery cell groups through the four hybrid/EV battery interface control modules. Voltage sense circuits are attached to each individual cell group, and these sense circuits terminate at a connector located on the top surface of the battery section. A serviceable auxiliary battery wiring harness joins this connector to a hybrid/EV battery interface control module, also located on the top surface of the battery section. The hybrid/EV battery interface control module encodes the voltage reading and transmits it to the battery energy control module through the battery control harness. There is one hybrid/EV battery interface control module located on battery sections one and two, and two hybrid/EV battery interface control modules associated with battery section three. The hybrid/EV battery interface control module, battery energy control module wiring harness, auxiliary battery wiring harness, and battery energy control module are all considered serviceable components.
The battery energy control module will determine when a fault condition is present. Diagnostics and system status are communicated from the battery energy control module to hybrid/EV powertrain control module 2 through serial data. The hybrid/EV powertrain control module 2 is the host controller for diagnostic trouble code information.

OBDII Code P1B18 GMC - Hybrid/Electric Vehicle Battery 27 Circuit High Voltage - AutoCodes.com — P1B18 GMC Code - Hybrid/Electric Vehicle Battery 27 Circuit High Voltage

What does this mean?

What are the Possible Causes of the DTC P1B18 GMC?

Faulty Hybrid/Electric Vehicle Battery Pack
Faulty Hybrid/Electric Vehicle Battery Interface Control Module

How to Fix the DTC P1B18 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 P1B18 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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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 P1B18 GMC Code

1. What are the common symptoms of OBDII code P1B18 in a GMC hybrid/electric vehicle?

- Common symptoms include reduced fuel efficiency, loss of power, and the illumination of the check engine light.

2. What are the possible causes of the OBDII code P1B18 in a GMC hybrid/electric vehicle?

- The code P1B18 typically indicates a high voltage issue in the Hybrid/Electric Vehicle Battery 27 Circuit, which could be caused by a faulty battery module, damaged wiring, or a problem with the battery management system.

3. How can I diagnose the OBDII code P1B18 in my GMC hybrid/electric vehicle?

- Proper diagnosis involves using a scan tool to read the code, inspecting the high voltage battery components, checking for loose connections, and testing the battery voltage levels.

4. Is it safe to continue driving with the OBDII code P1B18 in my GMC hybrid/electric vehicle?

- It is not recommended to drive the vehicle with this code present, as it can lead to further damage to the high voltage system and potentially unsafe driving conditions.

5. How can I repair the OBDII code P1B18 in my GMC hybrid/electric vehicle?

- Repairing the code may involve replacing a faulty battery module, repairing damaged wiring, or reprogramming the battery management system. It is recommended to have the repairs done by a qualified technician familiar with hybrid/electric vehicles.

6. Can I reset the OBDII code P1B18 in my GMC hybrid/electric vehicle on my own?

- While you can clear the code with a scan tool, it is important to address the underlying issue causing the code to prevent it from reoccurring.

7. Are there any preventive maintenance tips to avoid the OBDII code P1B18 in a GMC hybrid/electric vehicle?

- Regularly inspecting the high voltage battery components, following manufacturer's maintenance guidelines, and keeping up with battery health checks can help prevent issues leading to the P1B18 code.

8. How long does it typically take to repair the OBDII code P1B18 in a GMC hybrid/electric vehicle?

- The repair time can vary depending on the exact cause of the code and the availability of parts. It is recommended to consult with a professional technician for an accurate estimate.

9. Will the OBDII code P1B18 cause my GMC hybrid/electric vehicle to stop running?

- In some cases, the vehicle may go into a reduced power mode or may not start at all if the issue causing the code is severe. It is important to address the problem promptly to avoid further complications.

10. Can a DIY enthusiast with basic automotive knowledge tackle the repair for the OBDII code P1B18 in a GMC hybrid/electric vehicle?

- Due to the complexity of hybrid/electric vehicle systems and the high voltage nature of the issue, it is recommended to seek professional help for diagnosing and repairing the OBDII code P1B18 in a GMC hybrid/electric vehicle.