This guide is designed for mechanics, diagnostic technicians, or advanced DIYers. It covers the definition, technical explanation, common symptoms, causes, and a step-by-step repair procedure. 1. Code Definition Code: B173D Manufacturer: Peugeot / Citroën (PSA Group) System: Body Control Module (BCU/BSI) / Locking Architecture Description: Lock Assembly / Door Lock Signal Plausibility Error Variant: Often accompanied by suffixes like 5A (Upper Limit) or 4A (Signal Invalid). Xwapseries.fun - Avanthika Nair Uncut Extreme [BEST]