B1906 - FAULT CODE - OBD2

B1906 TOYOTA, SCION, LEXUS: OPEN IN FRONT PASSENGER SIDE PRETENSIONER SQUIB CIRCUIT

The circuit in charge of activating the front passenger side pretensioner includes the Center Airbag Sensor assembly and the outboard belt that corresponds to the right front seat (HR). The purpose of this circuit is to communicate the Supplemental Restraint System (SRS) when deployment is required once the conditions for such action are met.

The DTC B1906 OBD2 for Toyota, Lexus, and Scion vehicles relates to a fault with the front passenger side pretensioner activation circuit, and it is set when the circuit is open.

• Check Engine lamp illuminated.
• Airbag malfunction warning lamp illuminated.

The B1906 OBDII diagnostic code setting occurs because of the following reasons:

• The front seat right outboard (RH) belt circuit wiring could have some damage.
• The front seat right outboard seat belt (RH) circuit connections may be faulty, causing the open circuit.
• The front seat outboard belt (front passenger side pretensioner squib) may be defective.
• The Center Airbag Sensor assembly may be in poor condition.

Steps to follow to troubleshoot the B1906 OBD2 fault code are:

• Consult the Technical Service Bulletins as a first step.
• Check the wires and connectors related to the right outboard (RH) front seat belt circuit. Check they are in good condition. If deficiencies due to burns or wear are found, make the appropriate corrections.
• Using the appropriate tools, check the front seat right outer belt (RH) circuit for some damage. Compare the actual electrical values with those indicated by the manufacturer in their specifications. If the actual voltages are deficient, verify that it is not due to bad connections. Make the necessary repairs.
• Check that the right outer belt (RH) of the front seat is in good condition. For these tests, refer to the steps indicated by the manufacturer. If some damage is detected, make the right adjustments.