AutoCodes – Toyota – B1866 Toyota

B1866 Toyota Code - Open In Front Passenger Side Knee Airbag Squib Circuit

Quick Answer

The Front Passenger Side Knee Airbag Squib Circuit consists of the Airbag Sensor Assembly and the Front Passenger Side Knee Airbag Assembly. Common causes include Faulty Front Passenger Side Knee Airbag Assembly (Front Passenger Side Knee Squib), Front Passenger Side Knee Airbag Assembly harness is open or shorted, Front Passenger Side Knee Airbag Assembly circuit poor electrical connection. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

What it means: B1866 Toyota indicates Open In Front Passenger Side Knee Airbag Squib Circuit.
Common causes: Common causes include Faulty Front Passenger Side Knee Airbag Assembly (Front Passenger Side Knee Squib), Front Passenger Side Knee Airbag Assembly harness is open or shorted, Front Passenger Side Knee Airbag Assembly circuit poor electrical connection.
Severity: High - diagnose this code as soon as possible.
Can I drive?: Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

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Code Popularity 7,147

How popular is this code, among other codes? Low

Repair Importance Level

Urgent (Diagnose now) (3 / 3)

Repair Difficulty Level

Advanced (Pro) (3 / 3)

What is this?

Table of contents Created and updated by William Orellana on Jul 10, 2019

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code B1866 Toyota Description

The Front Passenger Side Knee Airbag Squib Circuit consists of the Airbag Sensor Assembly and the Front Passenger Side Knee Airbag Assembly. The circuit instructs the Supplemental Restraint System (SRS) to deploy when deployment conditions are met. The Diagnostic Trouble Code (DTC) is stored when a malfunction is detected in the Front Passenger Side Knee Airbag Squib Circuit.

OBDII Code B1866 Toyota - Open In Front Passenger Side Knee Airbag Squib Circuit - AutoCodes.com — B1866 Toyota Code - Open In Front Passenger Side Knee Airbag Squib Circuit

What does this mean?

What are the Possible Causes of the DTC B1866 Toyota?

Faulty Front Passenger Side Knee Airbag Assembly (Front Passenger Side Knee Squib)
Front Passenger Side Knee Airbag Assembly harness is open or shorted
Front Passenger Side Knee Airbag Assembly circuit poor electrical connection
Faulty Center Airbag Sensor Assembly

How to Fix the DTC B1866 Toyota?

Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the B1866 Toyota code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.

Need more information about the B1866 Toyota code?

Need more information on how to fix the B1866 Toyota code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the B1866 Toyota code diagnosed by a professional: Find a repair shop in your area

Precautions for SRS “AIR BAG” and “SEAT BELT PRE-TENSIONER” Service

Never probe the electrical connectors on air bag, side air curtain modules or seat belts.
Never disassemble or tamper with safety belt buckle/retractor pretensioners, adaptive load limiting retractors, safety belt inflators, or probe the electrical connectors.
Do not use electrical test equipment to check SRS circuits unless instructed to in this Service Manual.
Before servicing the SRS, turn ignition switch OFF, disconnect both battery cables and wait at least 3 minutes. For approximately 3 minutes after the cables are removed, it is still possible for the air bag and seat belt pre-tensioner to deploy. Therefore, do not work on any SRS connectors or wires until at least 3 minutes have passed.

Failure to follow this instruction may result in the accidental deployment of these modules, which increases the risk of serious personal injury or death.

About the author: William Orellana is a Master Mechanic and Mechanical Engineer with over 30 years of experience diagnosing and repairing vehicles. Learn more about his background.

Frequently Asked Questions about B1866 Toyota Code

1. What are the common symptoms of OBDII code B1866 in a Toyota related to an open in the front passenger side knee airbag squib circuit?

- The most common symptoms include the airbag warning light illuminating on the dashboard and a potential loss of functionality of the front passenger side knee airbag.

2. What can cause the OBDII code B1866 in a Toyota indicating an open in the front passenger side knee airbag squib circuit?

- The code B1866 is typically triggered by a break or disconnection in the wiring of the front passenger side knee airbag squib circuit.

3. How serious is OBDII code B1866 in a Toyota related to an open in the front passenger side knee airbag squib circuit?

- This code indicates a potential safety issue as it may affect the deployment of the front passenger side knee airbag during a collision, so it should be addressed promptly.

4. How can I diagnose the source of the open in the front passenger side knee airbag squib circuit triggering OBDII code B1866 in my Toyota?

- A thorough inspection of the wiring harness, connectors, and components associated with the front passenger side knee airbag squib circuit is necessary to identify the source of the open circuit.

5. Are there any DIY repair tips for fixing OBDII code B1866 in a Toyota due to an open in the front passenger side knee airbag squib circuit?

- DIY repair may be challenging due to safety concerns and the complexity of the airbag system. It is recommended to consult a professional mechanic or authorized service center for proper diagnosis and repair.

6. Can driving with OBDII code B1866 in a Toyota related to an open in the front passenger side knee airbag squib circuit be dangerous?

- Driving with this code unresolved may pose a risk in the event of a collision, as the front passenger side knee airbag may not deploy correctly to protect the occupant.

7. How much does it typically cost to repair OBDII code B1866 in a Toyota caused by an open in the front passenger side knee airbag squib circuit?

- The cost of repair can vary depending on the extent of the damage and the specific components that need to be replaced, but it may involve wiring repairs or component replacement.

8. Is it possible to reset or clear OBDII code B1866 in a Toyota related to an open in the front passenger side knee airbag squib circuit without fixing the underlying issue?

- Simply clearing the code without addressing the underlying open circuit issue will not solve the problem, and the code is likely to reappear once the vehicle is driven or the system is tested again.

9. How long does it typically take to repair OBDII code B1866 in a Toyota caused by an open in the front passenger side knee airbag squib circuit?

- The repair time can vary based on the extent of the damage and the accessibility of the affected components, but it may take a few hours to a full day for a professional mechanic to diagnose and fix the issue.

10. Can OBDII code B1866 in a Toyota related to an open in the front passenger side knee airbag squib circuit be prevented?

- Regular maintenance checks and timely repairs of any airbag system issues can help prevent the occurrence of OBDII code B1866 and ensure the proper functionality of the front passenger side knee airbag in a Toyota.