AutoCodes – GMC – P1A27 GMC

P1A27 GMC Code - Hybrid Battery 1 Voltage Very Low

Quick Answer

Battery voltage sensors allow the Energy Storage Control Module (ESCM) to monitor the voltage of the batteries in the Energy Storage Box (ESB). Common causes include Faulty Energy Storage Box (ESB) Battery, Faulty Battery Energy Control Module (BECM), Battery Energy Control Module (BECM) harness is open or shorted. 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: P1A27 GMC indicates Hybrid Battery 1 Voltage Very Low.
Common causes: Common causes include Faulty Energy Storage Box (ESB) Battery, Faulty Battery Energy Control Module (BECM), Battery Energy Control Module (BECM) harness is open or shorted.
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.

Save to My Repairs My Repairs

AI answers can be wrong. Verify repairs with testing. Open full chat

Code Popularity 799

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 Feb 15, 2020

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
Add Comment

💬 Need more help? Ask Coddy for instant answers — it's free!

Code P1A27 GMC Description

Battery voltage sensors allow the Energy Storage Control Module (ESCM) to monitor the voltage of the batteries in the Energy Storage Box (ESB). The batteries apply voltage to internal input resistors that are connected to the signal circuits of the battery voltage sensors. The module provides ground to the battery voltage sensors through the reference circuit. The ESCM monitors the voltage drop across the battery voltage sensors and uses the inputs for hybrid calculations. When the battery voltage is high, the resistances of the sensors are high and the voltage signals are high. When the battery voltage is low, the resistances of the sensors are low and the voltage signals are low.

OBDII Code P1A27 GMC - Hybrid Battery 1 Voltage Very Low - AutoCodes.com — P1A27 GMC Code - Hybrid Battery 1 Voltage Very Low

What does this mean?

What are the Possible Causes of the DTC P1A27 GMC?

Faulty Energy Storage Box (ESB) Battery
Faulty Battery Energy Control Module (BECM)
Battery Energy Control Module (BECM) harness is open or shorted
Battery Energy Control Module (BECM) circuit poor electrical connection

How to Fix the DTC P1A27 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 P1A27 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.

Need more information about the P1A27 GMC code?

Need more information on how to fix the P1A27 GMC code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P1A27 GMC code diagnosed by a professional: Find a repair shop in your area

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 P1A27 GMC Code

1. What are the common symptoms of OBDII code P1A27 GMC (Hybrid Battery 1 Voltage Very Low)?

The common symptoms include reduced electric propulsion power, difficulty starting the hybrid vehicle, and illuminated warning lights on the dashboard.

2. What are the possible causes of OBDII code P1A27 GMC (Hybrid Battery 1 Voltage Very Low)?

Possible causes include a faulty hybrid battery pack, damaged battery cells, issues with the battery management system, or a problem with the charging system.

3. How can I diagnose the issue related to OBDII code P1A27 GMC (Hybrid Battery 1 Voltage Very Low)?

Diagnosis typically involves using a diagnostic scan tool to read the code, checking the voltage levels of the hybrid battery cells, inspecting the battery connections, and testing the charging system.

4. Is it safe to continue driving with OBDII code P1A27 GMC (Hybrid Battery 1 Voltage Very Low) present?

It is not recommended to drive the vehicle with this code active as it can lead to further damage to the hybrid battery system and potentially affect the vehicle's performance.

5. Can I reset the OBDII code P1A27 GMC (Hybrid Battery 1 Voltage Very Low) by disconnecting the battery?

While disconnecting the battery may clear the code temporarily, it is essential to diagnose and address the underlying issue causing the low voltage to prevent the code from reoccurring.

6. What are some repair tips for resolving OBDII code P1A27 GMC (Hybrid Battery 1 Voltage Very Low)?

Repair tips may include replacing damaged battery cells, recalibrating the battery management system, ensuring proper charging system functionality, and seeking professional assistance if needed.

7. How much does it typically cost to repair OBDII code P1A27 GMC (Hybrid Battery 1 Voltage Very Low)?

The cost of repair can vary depending on the extent of the issue, the need for battery replacement, and labor costs. It is recommended to obtain quotes from reputable automotive technicians or dealerships.

8. Can OBDII code P1A27 GMC (Hybrid Battery 1 Voltage Very Low) be a recurring issue?

Yes, if the underlying cause of the low voltage is not addressed, the code may reoccur, leading to ongoing problems with the hybrid battery system.

9. Are there any preventive measures to avoid OBDII code P1A27 GMC (Hybrid Battery 1 Voltage Very Low)?

Regular maintenance of the hybrid battery system, monitoring voltage levels, and addressing any warning signs promptly can help prevent issues that trigger this OBDII code.

10. Should I attempt to repair OBDII code P1A27 GMC (Hybrid Battery 1 Voltage Very Low) myself?

Due to the complexity of hybrid vehicle systems and the potential safety risks involved, it is recommended to seek professional assistance or consult with a certified automotive technician for proper diagnosis and repair of this code.