48V Lithium-Ion Battery Cell Voltage Imbalance
2012-2019 Fiat 500 1.4L I4
Description
One or more cells in the 48V lithium-ion battery have voltage that deviates significantly from other cells in the pack.
Symptoms
- 48V system limited
- Mild hybrid features intermittent
- 48V battery not holding charge
- Warning indicator for 48V system
- Reduced energy recovery
Common Causes
- Individual cell degradation
- Cell manufacturing variation
- Temperature gradient across pack
- BMS balancing circuit failure
- Extended storage without maintenance charge
Diagnostic Steps
- Read individual 48V cell voltages
- Check cell voltage spread
- Monitor balancing activity
- Test 48V battery temperature uniformity
- Review battery age and usage history
Repair Notes
Replace 48V battery pack if cell imbalance exceeds threshold. 48V batteries are typically replaced as a complete unit.
Related Codes
Other Powertrain Codes
- P0001Fuel Volume Regulator Control Circuit/Open
- P0002Fuel Volume Regulator Control Circuit Range/Performance
- P0003Fuel Volume Regulator Control Circuit Low
- P0004Fuel Volume Regulator Control Circuit High
- P0010Intake Camshaft Position Actuator Circuit/Open Bank 1
- P0011Intake Camshaft Position Timing Over-Advanced Bank 1
- P0012Intake Camshaft Position Timing Over-Retarded Bank 1
- P0013Exhaust Camshaft Position Actuator Circuit/Open Bank 1
- P0014Exhaust Camshaft Position Timing Over-Advanced Bank 1
- P0015Exhaust Camshaft Position Timing Over-Retarded Bank 1
P3808 on Other Vehicles
Fiat 124 Spider
2017-2020 1.4L I4 Turbo
Fiat 500 Abarth
2012-2019 1.4L I4 Turbo
Fiat 500 BR
2011-2020 1.4L I4 Flex Fire Evo
Fiat 500 PL
2007-2025 1.0L I3 Hybrid FireFly 70
Fiat 500 PL
2007-2025 1.2L I4 Fire 69
Fiat 500L
2014-2020 1.4L I4 Turbo
Fiat 500X
2016-2024 1.4L I4 Turbo
Fiat Argo
2017-2025 1.0L I4 Flex Firefly
Common Questions
What does code P3808 mean on a 2012-2019 Fiat 500?
P3808 stands for "48V Lithium-Ion Battery Cell Voltage Imbalance". One or more cells in the 48V lithium-ion battery have voltage that deviates significantly from other cells in the pack.
What are the symptoms of P3808 on a Fiat 500?
Common symptoms of P3808 include: 48V system limited, Mild hybrid features intermittent, 48V battery not holding charge, Warning indicator for 48V system, Reduced energy recovery.
What causes P3808 on a 2012-2019 Fiat 500?
Common causes of P3808 include: Individual cell degradation, Cell manufacturing variation, Temperature gradient across pack, BMS balancing circuit failure, Extended storage without maintenance charge.