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2019 AUDI A6
3.0L V6 TFSI•AWD•AUTOMATIC•gas•supercharged
7 active safety recalls on this vehicle — view recalls
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Repairs0Labor495Torque4326Fluid9DTC1145Battery1Maintenance0Recalls7
P3808high severityPowertrain

48V Lithium-Ion Battery Cell Voltage Imbalance

on 2019 Audi A6 3.0L V6 TFSI · AWD

What this code means

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

  1. Read individual 48V cell voltages
  2. Check cell voltage spread
  3. Monitor balancing activity
  4. Test 48V battery temperature uniformity
  5. 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.

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