B173d Peugeot (720p)
The B173D Peugeot code is a classic, predictable failure on modern Peugeot, Citroen, and DS diesel engines. While the code sounds like a complex body control module error, it is almost always a simple electrical fault in the cylinder 4 glow plug circuit.
Do not ignore it. A $40 glow plug and an hour of careful labor today will save you from a $2,000 cylinder head repair tomorrow. If you are uncomfortable removing glow plugs from a hot engine (given their tendency to snap), pay an independent diesel specialist who has experience with Peugeot BlueHDi engines.
Remember the golden rule of owning a modern diesel: Respect the glow plugs, or they will command a heavy price.
Disclaimer: This article is for informational purposes only. Always consult your vehicle's service manual and follow safety procedures. Torque specifications vary by engine code (DV6C, DV6D, DW10).
B173D Peugeot: A Rare and Elusive Error Code
The B173D Peugeot error code is a mysterious and uncommon fault code that has left many Peugeot owners and mechanics scratching their heads. This write-up aims to provide an in-depth look at this enigmatic error code, its possible causes, and potential solutions.
What is the B173D Peugeot error code?
The B173D Peugeot error code is a manufacturer-specific code that refers to a problem with the vehicle's electrical system. Specifically, it relates to a fault in the "Passenger Seat Belt Not Fastened" signal. This code is usually accompanied by a warning light on the dashboard, indicating that there's an issue with the seat belt system.
Possible Causes of the B173D Peugeot Error Code
Several factors can contribute to the B173D Peugeot error code:
Symptoms of the B173D Peugeot Error Code
If your Peugeot vehicle is displaying the B173D error code, you may experience the following symptoms:
Solutions to the B173D Peugeot Error Code b173d peugeot
To resolve the B173D Peugeot error code, try the following:
In conclusion, the B173D Peugeot error code is a complex issue that requires attention to the vehicle's electrical system and seat belt system. By understanding the possible causes and symptoms, you can take the necessary steps to resolve the issue and get back on the road. If you're unsure about how to proceed, it's always best to consult a qualified mechanic or a Peugeot specialist.
In Peugeot and Citroën vehicles, is not a feature but a specific diagnostic fault code (DTC) related to the vehicle's security system Fault Code Definition indicates a failure in identifying the mechanical/electronic key
or the hands-free remote control. It essentially means the car's central computer, known as the BSI (Body Systems Interface)
, cannot communicate with or verify the key currently being used. Common Symptoms
When this fault code is active, you may experience the following issues: "Key Not Detected" warning on the dashboard. Engine starting issues
: The vehicle may crank but fail to start, or it may not respond to the start button/ignition at all. Central locking failure : The remote may fail to lock or unlock the doors. Potential Causes and Solutions
The issue can range from simple battery problems to hardware failures: Weak Key Fob Battery
: Replacing the battery in your remote is the first recommended step. Immobilizer Antenna
: The reader/antenna located around the ignition or in the center console might be faulty and unable to "read" the key. BSI Software Error
: Sometimes the car's computer needs a reset. This can often be fixed by a BSI Reboot
, which involves a specific battery disconnection and reconnection sequence known as the "3-minute rule". Wiring Issues The B173D Peugeot code is a classic, predictable
: Damage to the wiring between the key reader and the BSI can prevent the identification signal from reaching the computer. Further Exploration Learn the exact steps for a Peugeot BSI Reboot to clear temporary software glitches. View a detailed explanation of Citroën/Peugeot immobilizer faults on Facebook for visual diagnostic tips. French Car Forum
for original user reports and community-sourced fixes for B173D and related electrical errors. Are you seeing this code on a specific Peugeot model , and does the car currently start Electrical circuit fault: have your vehicle repaired
In the context of Peugeot and Citroën (PSA Group) vehicles, the fault code B173D is a diagnostic trouble code (DTC) that signifies a failure in identifying the mechanical or electronic key, or the remote control. Understanding Fault Code B173D
This code is categorized as a "Body" code, typically managed by the BSI (Built-in Systems Interface), which is the central control unit for the vehicle's electronic functions. When this fault is active, the vehicle's immobilizer system fails to recognize the authorized signal from the key fob, leading to several operational issues. Primary Symptoms:
Engine Non-Start: The engine may fail to crank or start because the immobilizer remains active.
Key Not Detected: A warning message such as "Key not detected" or "Electronic anti-theft faulty" may appear on the dashboard.
Intermittent Starting: The car might start occasionally but fail at other times, often during specific weather conditions or after the vehicle has been sitting.
Central Locking Issues: Difficulties locking or unlocking the vehicle remotely. Common Causes
The failure to identify the key can stem from several localized or systemic issues:
Key Fob Battery: A weak or dead battery in the remote control is the most frequent cause.
Key Reader/Antenna: The internal antenna or the key reader unit (often located near the ignition or in the center console for hands-free systems) may be faulty or disconnected.
Electrical Interference: Proximity to other electronic devices or low vehicle battery voltage can disrupt the signal. Symptoms of the B173D Peugeot Error Code If
Wiring/BSI Communication: Corroded wiring or a software glitch in the BSI can prevent the key's ID from being correctly processed. Recommended Steps for Resolution
Replace the Key Fob Battery: This is the simplest and cheapest first step.
Try a Spare Key: If the car starts with a second key, the issue is isolated to the original key fob.
Check Vehicle Battery Voltage: Low voltage in the main car battery can cause "ghost" faults in the BSI. Ensure the battery is fully charged (typically above 12.7V when off).
Perform a BSI Reset: This "soft reset" of the car's computer can sometimes clear temporary communication glitches. A standard procedure involves disconnecting the battery following a specific sequence (e.g., waiting for the system to go to "sleep" before disconnecting).
Professional Diagnostic: If the above steps fail, use a dedicated diagnostic tool (like Diagbox) to check for deeper BSI or wiring faults.
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If the glow plug tests fine electrically, but the code persists, you may have carbon "bridging." The mechanic must:
This is the #1 cause of B173D in Peugeots. If the battery was disconnected or replaced recently without following the correct "Sleep Mode" procedure, the BSI can lose its configuration or corrupt the data handshake with other modules.
Modern Peugeots are equipped with an automatic climate control system. When you set the HVAC to "Auto," the system monitors outside air quality. If the sensor detects high levels of pollutants (diesel fumes, CO, NOx), it automatically switches the ventilation from fresh air to recirculation mode to protect the cabin occupants.
The b173d code indicates that the Body Control Module (BSI) or the Climate Control Unit is not receiving a valid signal from this sensor.
Depending on the diagnosis, the solution will usually be one of the following:
An ounce of prevention is worth a pound of cure.