OBD Guide

B1C4C

1st Row Passenger Seat Belt Buckle Tensioner Circuit Low

B1C4C is an OBD-II diagnostic trouble code meaning: 1st Row Passenger Seat Belt Buckle Tensioner Circuit Low. Common causes: oxidation or corrosion of contacts in the pretensioner connector, damaged or broken pretensioner circuit harness. Estimated repair cost: $33–278.

Severity
🔴 High
Can you drive?
Limited driving only, diagnose soon
Approx. repair cost
$33–278 (est.)

Symptoms

  • The security system malfunction indicator on the dashboard is on
  • Error code B1C4C in the control module memory
  • Possible inability to activate the pretensioner during a collision
  • Unstable operation of the passenger passive safety system

Causes

  • Oxidation or corrosion of contacts in the pretensioner connector
  • Damaged or broken pretensioner circuit harness
  • Malfunction of the pretensioner solenoid or squib
  • Loose electrical connection at battery terminals
  • Low voltage on-board network of the car
  • Security control module malfunction
  • Pretensioner circuit fuse is broken or blown
  • Incorrect installation or replacement of the seat belt

How to Fix

  1. Connect a diagnostic scanner and check the full list of error codes
  2. Check the voltage of the on-board network - it should be 12-14 volts with the engine running
  3. Visually inspect the pretensioner wiring harness for damage or chafing.
  4. Check the pretensioner connector for oxidation and clean the contacts with alcohol
  5. Measure the pretensioner circuit resistance using a multimeter
  6. Check the condition of the security fuse and replace if necessary
  7. Make sure the harness is securely connected to the restraint control module.
  8. Replace pretensioner or wiring harness if necessary
  9. Clear error memory and test drive to check

Related codes

FAQ

What does the B1C4C code mean?

B1C4C is an OBD-II diagnostic trouble code that indicates: 1st Row Passenger Seat Belt Buckle Tensioner Circuit Low

What causes a B1C4C error code?

The most common causes of B1C4C include: Oxidation or corrosion of contacts in the pretensioner connector; Damaged or broken pretensioner circuit harness; Malfunction of the pretensioner solenoid or squib; Loose electrical connection at battery terminals.

How do I fix a B1C4C diagnostic trouble code?

To fix B1C4C: Connect a diagnostic scanner and check the full list of error codes. Check the voltage of the on-board network - it should be 12-14 volts with the engine running. Visually inspect the pretensioner wiring harness for damage or chafing.. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with B1C4C?

Limited driving only, diagnose soon

How much does it cost to fix B1C4C?

The estimated repair cost for B1C4C is $33–278. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat