in a Peugeot or Citroën (PSA Group) vehicle indicates a permanent or intermittent fault in identifying the mechanical/electronic key or the hands-free remote control present in the reader (identifier invalid) .
Yes, in most cases the vehicle remains drivable. However, the immobiliser may sometimes prevent starting, so it is advisable to resolve the issue promptly.
The BSI logs B173D , halts the engine starting authorization output, and prevents the Engine ECU from disabling the immobilizer. Common Symptoms of B173D
(mobile phones, NFC devices) that could interfere with the transponder signal.
The car fails to lock or unlock via the key fob. b173d peugeot work
Acquire your vehicle's backup or spare key. If the spare key starts the engine flawlessly and does not throw the B173D code, your primary key fob has a damaged internal transceiver circuit board or has lost its specific pairing configuration. It will need to be re-programmed or replaced by an auto locksmith. Step 3: Check Main Vehicle 12V Battery Voltage
Disclaimer: This information is for informational purposes only. Working on vehicle electronics can be risky. If unsure, consult a qualified technician.
from your Peugeot without adequate voltage protection.
If these steps don't work, you may need a professional diagnostic tool like Lexia/Diagbox to re-program the keys or check for wiring faults. in a Peugeot or Citroën (PSA Group) vehicle
: If the vehicle starts with a second key, the issue is likely a damaged transponder in the original key or a dead fob battery. Check Vehicle Battery Voltage
It started on a Tuesday morning. You go to start your Peugeot 308, but instead of the familiar engine rumble, the dashboard flashes a "Key Not Detected" warning. You try again, and it starts—but now the central locking is acting up, and a persistent Engine Management warning light has appeared. The Diagnostic Rabbit Hole
If you have scanned your car using a tool like Diagbox, Lexia, or a high-end multi-brand scanner and found B173D, use this systematic approach to fix it:
BSI (Body Control Unit), Immobilizer, Keyless Entry Antenna/Receiver. 3. Common Causes The BSI logs B173D , halts the engine
If you have a second key, try it. If the second key works, the issue is with your primary key fob. 3. Check the Car Battery
: The car might work flawlessly for weeks, and then randomly fail to recognize the key, forcing you to lock, unlock, and wait before it resets.
Fault in identifying mechanical/electronic key or hands-free remote control present in reader – Identifier Invalid.