AutoCodes – Toyota – B1856 Toyota

B1856 Toyota Code - Open In Rear Side Squib Left Circuit

Quick Answer

The Rear Side Squib Left (LH) Circuit consists of the Center Airbag Sensor Assembly and the Rear Seat Side Airbag Assembly Left (LH). Common causes include Faulty Rear Seat Side Airbag Assembly Left (LH) (Rear Side Squib Left Circuit), Rear Seat Side Airbag Assembly Left harness is open or shorted, Rear Seat Side Airbag Assembly Left 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: B1856 Toyota indicates Open In Rear Side Squib Left Circuit.
Common causes: Common causes include Faulty Rear Seat Side Airbag Assembly Left (LH) (Rear Side Squib Left Circuit), Rear Seat Side Airbag Assembly Left harness is open or shorted, Rear Seat Side Airbag Assembly Left 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.

Save to My Repairs My Repairs

AI answers can be wrong. Verify repairs with testing. Open full chat

Code Popularity 12,076

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 08, 2019

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
Add Comment

💬 Need more help? Ask Coddy for instant answers — it's free!

Code B1856 Toyota Description

The Rear Side Squib Left (LH) Circuit consists of the Center Airbag Sensor Assembly and the Rear Seat Side Airbag Assembly Left (LH). 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 Rear Side Squib Left Circuit.

OBDII Code B1856 Toyota - Open In Rear Side Squib Left Circuit - AutoCodes.com — B1856 Toyota Code - Open In Rear Side Squib Left Circuit

What does this mean?

What are the Possible Causes of the DTC B1856 Toyota?

Faulty Rear Seat Side Airbag Assembly Left (LH) (Rear Side Squib Left Circuit)
Rear Seat Side Airbag Assembly Left harness is open or shorted
Rear Seat Side Airbag Assembly Left circuit poor electrical connection
Faulty Center Airbag Sensor Assembly

How to Fix the DTC B1856 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 B1856 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 B1856 Toyota code?

Need more information on how to fix the B1856 Toyota code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the B1856 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 B1856 Toyota Code

1. What are the common symptoms of OBDII code B1856 Toyota (Open In Rear Side Squib Left Circuit)?

The common symptoms include the airbag warning light on the dashboard staying illuminated, failure of the airbag system to deploy in case of an accident, and possible diagnostic trouble codes related to the airbag system.

2. What are the potential causes of OBDII code B1856 Toyota?

The code B1856 indicates an open circuit in the rear side squib left circuit. Common causes include damaged wiring harness, loose connections, faulty airbag squib, or issues with the airbag control module.

3. How can I diagnose the issue related to OBDII code B1856 Toyota?

Diagnosing the problem involves conducting a thorough inspection of the wiring harness, connectors, and components in the rear side squib left circuit. Using a multimeter to test for continuity and resistance can help pinpoint the fault.

4. Can I repair OBDII code B1856 Toyota on my own?

While some DIY enthusiasts may attempt to repair the issue themselves, it is recommended to seek assistance from a professional mechanic or technician with experience in airbag system repairs due to the critical safety implications involved.

5. Is it safe to drive my Toyota with OBDII code B1856 present?

Driving with an unresolved airbag system issue can be risky as the airbags may not deploy in case of an accident. It is advisable to address the problem promptly to ensure the proper functioning of the safety systems.

6. How much does it typically cost to repair OBDII code B1856 Toyota?

The cost of repairs can vary depending on the exact cause of the issue, labor rates in your area, and whether any components need to be replaced. It is recommended to obtain quotes from different repair shops for an accurate estimate.

7. Can resetting the OBDII code B1856 Toyota clear the issue?

Resetting the code may temporarily turn off the warning light, but it will not fix the underlying problem causing the code. It is important to diagnose and repair the issue to ensure the proper functioning of the airbag system.

8. Are there any preventive measures to avoid OBDII code B1856 Toyota in the future?

Regular maintenance and inspections of the airbag system, including checking for loose connections and damaged wiring, can help prevent issues like OBDII code B1856 from occurring. Addressing any warning signs promptly is crucial.

9. How long does it take to repair OBDII code B1856 Toyota?

The repair time can vary depending on the exact cause of the issue, availability of parts, and the expertise of the technician. It is advisable to consult with the repair shop for an estimated time frame for the repair.

10. Can OBDII code B1856 Toyota be caused by a blown fuse?

While a blown fuse can potentially cause issues with the airbag system, OBDII code B1856 specifically points to an open circuit in the rear side squib left circuit. Checking and replacing any blown fuses is a good initial troubleshooting step.