AutoCodes – Toyota – B1878 Toyota

B1878 Toyota Code - Short to Positive in Passenger Side Front Seat Cushion Squib Circuit

Quick Answer

The Front Seat Cushion Squib Right (RH) Circuit consists of the Center Airbag Sensor Assembly and the Front Seat Airbag Sub-Assembly. Common causes include Faulty Front Seat Airbag Sub-Assembly (Front Seat Cushion Squib Right), Front Seat Airbag Sub-Assembly harness is open or shorted, Front Seat Airbag Sub-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: B1878 Toyota indicates Short to Positive in Passenger Side Front Seat Cushion Squib Circuit.
Common causes: Common causes include Faulty Front Seat Airbag Sub-Assembly (Front Seat Cushion Squib Right), Front Seat Airbag Sub-Assembly harness is open or shorted, Front Seat Airbag Sub-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 434

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 Dec 02, 2022

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code B1878 Toyota Description

The Front Seat Cushion Squib Right (RH) Circuit consists of the Center Airbag Sensor Assembly and the Front Seat Airbag Sub-Assembly. This 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 Seat Cushion Squib Right (RH).

OBDII Code B1878 Toyota - Short to Positive in Passenger Side Front Seat Cushion Squib Circuit - AutoCodes.com — B1878 Toyota Code - Short to Positive in Passenger Side Front Seat Cushion Squib Circuit

What does this mean?

What are the Possible Causes of the DTC B1878 Toyota?

Faulty Front Seat Airbag Sub-Assembly (Front Seat Cushion Squib Right)
Front Seat Airbag Sub-Assembly harness is open or shorted
Front Seat Airbag Sub-Assembly circuit poor electrical connection
Faulty Center Airbag Sensor Assembly

How to Fix the DTC B1878 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 B1878 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 B1878 Toyota code?

Need more information on how to fix the B1878 Toyota code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the B1878 Toyota code diagnosed by a professional: Find a repair shop in your area

Information for Specific Toyota Models

B1878 2013 Toyota RAV4 — Short to Positive in Passenger Side Front Seat Cushion Squib Circuit
B1878 2014 Toyota RAV4 — Short to Positive in Passenger Side Front Seat Cushion Squib Circuit
B1878 2015 Toyota RAV4 — Short to Positive in Passenger Side Front Seat Cushion Squib Circuit
B1878 2016 Toyota RAV4 — Short to Positive in Passenger Side Front Seat Cushion Squib Circuit
B1878 2017 Toyota RAV4 — Short to Positive in Passenger Side Front Seat Cushion Squib Circuit
B1878 2018 Toyota RAV4 — Short to Positive in Passenger Side Front Seat Cushion Squib Circuit

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 B1878 Toyota Code

1. What are common symptoms of OBDII code B1878 in a Toyota?

- Common symptoms include the airbag warning light being illuminated on the dashboard and possible issues with the passenger side front airbag system.

2. What does the OBDII code B1878 indicating "Short to Positive in Passenger Side Front Seat Cushion Squib Circuit" mean?

- This code suggests that there is a short circuit to positive in the passenger side front seat cushion airbag system.

3. What are possible causes of OBDII code B1878 in a Toyota?

- Possible causes include damaged wiring, a faulty seat cushion squib, a malfunctioning airbag control module, or loose connections in the system.

4. How can I diagnose the issue related to OBDII code B1878 in my Toyota?

- To diagnose the issue, you may need to perform a thorough inspection of the wiring, connectors, seat cushion squib, and airbag control module. Using a diagnostic scanner can help pinpoint the exact problem.

5. Can I continue driving my Toyota with OBDII code B1878 present?

- It is not recommended to drive the vehicle with this code present, as it indicates a potential issue with the passenger side airbag system, which may not deploy properly in the event of a collision.

6. How can I repair OBDII code B1878 in a Toyota?

- Repairing this code may involve fixing the short circuit, replacing damaged wiring or components, or resetting the airbag system using a diagnostic scanner.

7. Is it safe to reset the OBDII code B1878 without fixing the underlying issue?

- It is not safe to reset the code without addressing the underlying problem, as it may compromise the functionality of the passenger side airbag system.

8. Can I fix OBDII code B1878 in my Toyota by myself, or do I need professional help?

- Depending on your experience and knowledge of automotive electrical systems, you may be able to fix the issue yourself. However, it is recommended to seek professional help if you are unsure or unfamiliar with airbag system repairs.

9. How much does it typically cost to repair OBDII code B1878 in a Toyota?

- The cost of repair can vary depending on the exact cause of the issue and the parts and labor required. It is advisable to get a diagnostic assessment from a certified mechanic to determine the cost accurately.

10. Are there any recalls or technical service bulletins related to OBDII code B1878 in Toyota vehicles?

- It is always a good idea to check with Toyota dealerships or visit the National Highway Traffic Safety Administration (NHTSA) website to see if there are any recalls or technical service bulletins related to this specific OBDII code in Toyota vehicles.