The 48V battery in modern vehicles such as the VW Golf 8 is a vital part of the mild hybrid system, which helps to save fuel and provides an improved driving experience. However, as with any complex system, problems can occur. In this blog we will cover the most common faults, error codes, repair processes, and provide insight into the costs of repair. This can be useful for garages that have to deal with vehicles equipped with a 48V battery.
What does the 48V battery do?
The 48V battery in the VW Golf 8 is linked to the mild hybrid system (MHEV). It supports the combustion engine by, among other things, supplying electrical energy during acceleration and enabling "coasting" (rolling out without engine load). This reduces fuel consumption and emissions. Problems with this battery can, however, lead to loss of these functions, and even to more serious malfunctions.
Common Malfunctions
There are a number of problems that often occur with the 48V battery:
1. Battery not charging
The battery does not charge properly while driving. This problem can be caused by a defective voltage regulator, cables, or the battery itself.
2. Battery loses capacity
Over time, the battery capacity may decrease. This may result in reduced power from the mild hybrid system and increased fuel consumption.
3. Belt Driven Starter Generator Problems
The belt-driven starter generator is responsible for converting energy between the engine and the 48V battery. Defects in this component can lead to the mild hybrid functions not functioning properly.
Error Codes and Diagnostics
When problems occur with the 48V battery, specific error codes can help diagnose the problem. Some common error codes for the VW Golf 8 are:
- P0A80 : Hybrid/EV battery error
- P1A14 : Error in the 48V battery cell
- P0CA1 : Voltage difference in the 48V battery
- P1A0F : Battery module temperature too high or too low
Using an OBD2 scanner can help read these fault codes and make a targeted diagnosis.
Part Numbers
When replacing parts in the 48V battery and hybrid system, the following OEM part numbers are relevant for the VW Golf 8:
- Part number Battery 48V: 5Q0915105J
- Belt-driven starter-generator: 04L903023Q
- Voltage regulator: 04L903023P
You will find this battery, 5Q0915105J, with the following brands/models
1. Volkswagen
- Volkswagen Golf 8 (Mild-hybrid models)
- Volkswagen Passat (Mild-hybrid versions)
- Volkswagen Tiguan (MHEV models)
2. Audi
- Audi A3 (MHEV versions)
- Audi A4 (MHEV models)
- Audi A6 (Mild-hybrid models)
- Audi Q5 (Mild-hybrid versions)
- Audi Q7 (Mild-hybrid versions)
- Audi A7 (MHEV models)
3. Seat
- Seat Leon (MHEV versions)
- Seat Tarraco (MHEV models)
4. Škoda
- Škoda Octavia (MHEV versions)
- Škoda Superb (MHEV models)
- Škoda Kodiaq (Mild-hybrid versions)
- Škoda Karoq (MHEV models)
Repair and Costs
The cost of repairing a 48V system in a VW Golf 8 can vary depending on the severity of the problem. Below we provide an overview of common repairs:
1Battery repair: The 48V battery itself costs between €600 and €1,200, excluding labor costs. The replacement usually takes 2-3 hours, which can amount to €250 in labor costs depending on the garage's rate.
Prevention is better than cure
Regular maintenance of the 48V system, including checking the condition of the battery and cable connections, can help prevent problems. Advise customers to have the system checked as soon as possible if there are signs of reduced performance.
Conclusion
It is important for garages to be aware of the possible problems with the 48V battery in the VW Golf 8. The right diagnostic tools, combined with knowledge of error codes and common faults, can save time and money. Preventative maintenance and prompt repairs can keep customers happy and prevent more serious, expensive repairs.