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B191604 — Backup battery, Faulty

Backup battery, Faulty. The Taycan, 911 (992), Panamera (971), Panamera (972) and Cayenne report this code; below is which control unit sets it on each model and how to read and clear it.

Which models and control units set B191604

Porsche Taycan

Telematics Communication UnitTelematics Diagnostic Unit

Porsche 911 (992)

Telematics Communication Unit

Porsche Panamera (971, 2017–2023)

GatewayTelematics Communication UnitTelematics Diagnostic Unit

Porsche Panamera (972, 2024–)

Telematics Communication UnitTelematics Diagnostic Unit

Porsche Cayenne (9YA)

GatewayTelematics Communication UnitTelematics Diagnostic Unit

How to read and clear B191604

  1. Plug a standard ENET (Ethernet-to-OBD) cable into your Porsche's OBD port and your Mac or Windows PC.
  2. Open STEUER14, pick your car and run a fault scan: every control unit is read, and B191604 shows with its status, its full description and the freeze frame when the unit stores one.
  3. Fix the cause first, then clear the fault memory and scan again to check it stays away. Reading and clearing fault codes is free on every control unit.

More about fault memory in the manual →

Download STEUER14 — free fault reading

Other codes of the Telematics Communication Unit

B18DDF3Emergency call test mode, Backup battery function restriction
B18DDF4Emergency call test mode, LED display function restriction
B18DDF5Emergency call test mode, Emergency call button function restriction
B18F4F0Crash signal from airbag control module, implausible
B18F4F1Crash signal from airbag control module, permanently on high level
B18F4F2Crash signal from airbag control module, permanently on low level
B1916F0Backup battery, Critical charge level
B1916F1Backup battery, Not recognized
B1916F4Backup battery, Service life critical
B1916F5Backup battery, Service life exceeded
B1A2FF1Bluetooth Low Energy antenna, communication error
B1A6711Mobile communications antenna 4 for emergency call module and communications unit, Short circuit to ground

All 157 codes of this control unit →

Fault names come from the manufacturer's diagnostic data. STEUER14 is independent and not affiliated with Porsche AG. A code tells you what a control unit detected, not always which part failed — check wiring, supply voltage and related codes before replacing parts. STEUER14 shows each fault's full description, status and freeze frame on the car.