Unlike engine-related codes (P-codes), B-codes (Body codes) can be more intimidating to diagnose. This article will explain everything you need to know about the , from its precise technical definition to step-by-step diagnostic and repair procedures.
Essentially, this code implies that the Body Control Module (BSI— Boîtier de Servitude Intelligent ) is unable to communicate correctly with the heating and ventilation control unit, or the software configuration data for the HVAC system is missing, corrupted, or incompatible. It is a "communication/configuration" error rather than a mechanical failure like a broken window or a burnt-out motor. b173d peugeot
| Code | Meaning | Typical Fix | | --- | --- | --- | | | Driver airbag – resistance too high | Clockspring or connector | | B173C | Driver airbag – resistance too low (short circuit) | Short in wiring or airbag | | B1741 | Passenger airbag – resistance too high | Connector under seat | | U1F1A | Lost communication with airbag ECU | BCM or CAN bus issue | It is a "communication/configuration" error rather than a
The climate control system communicates via the CAN (Controller Area Network) bus. If there is corrosion in the wiring harness, a bent pin in a connector, or water ingress (common in Peugeots due to scuttle panel leaks), the data packets between the HVAC and BSI can become scrambled. While you can’t stop a clockspring from aging,
While you can’t stop a clockspring from aging, you can reduce risks:
Do not confuse B173D with a general communication error. Your diagnostic tool must state “high resistance” specifically.