B173d Peugeot Work Site
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).
In simple terms, this code indicates that the Body Control Module (BSI) has detected a discrepancy between the command sent to the door lock and the status signal returned by the door lock mechanism. The BSI commands the door to lock, but the feedback circuit tells the BSI the door is still unlocked (or vice versa).
| Cause | Fix | |-------|-----| | Loose yellow connector under seat | Clean contacts, apply silicone grease, reseat firmly | | Clock spring failed | Replace spiral cassette (€50–120 part, 1 hour DIY) | | Broken wire at steering column | Solder & heatshrink repair (or replace harness) | | Airbag module connector bent pins | Carefully straighten or replace connector |
After repair: Clear codes with OBD2 / PP2000 diagnostic tool (generic scanners may not reset SRS codes – need Diagbox / Lexia). b173d peugeot work
Symptom: Intermittent limp mode, B173D stored.
Attempted fix (outside garage): New battery, new glow plugs – no change.
Our diagnosis: Measured relay coil resistance – open circuit. Replaced pre-heat relay ($35). B173D returned after 3 days.
Root cause: Relay socket corrosion caused heat damage to the new relay.
Final work: Replaced entire BPGA unit and both relays. Executed BMS reset.
Result: 6 months, 8,000 miles – no reoccurrence.
This case proves that simply changing the relay is often insufficient. The entire circuit must be evaluated.
This is critical. A battery with a dead cell (voltage drops below 10V during cranking) will trigger B173D falsely. Code: B173D Manufacturer: Peugeot / Citroën (PSA Group)
If you own a modern Peugeot vehicle (such as the 208, 2008, 308, or 3008) and your dashboard has illuminated a warning light accompanied by a drop in performance, you may have seen the cryptic fault code B173D appear on a diagnostic scanner. For mechanics and DIY enthusiasts alike, the phrase “b173d peugeot work” has become a common search query, signaling a specific, repeatable electrical issue.
But what exactly does code B173D mean? Why does it require immediate attention? And most importantly, what does the “work” involve to fix it permanently? This article provides a deep dive into the B173D fault—from technical definition to step-by-step repair procedures.
Remove the lock assembly from the door. Use a multimeter to test the pins on the lock connector (refer to a wiring diagram for your specific model, typically 4 to 6 pins): | Cause | Fix | |-------|-----| | Loose
Once you’ve completed the b173d peugeot work, follow these rules:
Use your diagnostic tool to access the Built-In Systems Interface (BSI).