AutoCodesFord – B1939 Ford

B1939 Ford Code - Air Bag Passenger Pressure Switch Circuit Short To Ground Fault

Quick Answer

The Restraints Control Module (RCM) monitors the Air Bag Passenger Pressure Switch. Common causes include Faulty Air Bag Passenger Pressure Switch, Air Bag Passenger Pressure Switch harness is open or shorted, Air Bag Passenger Pressure Switch 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
B1939 Ford indicates Air Bag Passenger Pressure Switch Circuit Short To Ground Fault.
Common causes
Common causes include Faulty Air Bag Passenger Pressure Switch, Air Bag Passenger Pressure Switch harness is open or shorted, Air Bag Passenger Pressure Switch 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.
AI answers can be wrong. Verify repairs with testing. Open full chat
Code Popularity 857
How popular is this code, among other codes? Low
Table of contents Created and updated by William Orellana on Jul 29, 2019
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Code B1939 Ford Description

The Restraints Control Module (RCM) monitors the Air Bag Passenger Pressure Switch. The RCM sets the OBDII code when the Air Bag Passenger Pressure Switch is not to factory specifications.
OBDII Code B1939 Ford - Air Bag Passenger Pressure Switch Circuit Short To Ground Fault - AutoCodes.com
B1939 Ford Code - Air Bag Passenger Pressure Switch Circuit Short To Ground Fault

What are the Possible Causes of the DTC B1939 Ford?

  • Faulty Air Bag Passenger Pressure Switch
  • Air Bag Passenger Pressure Switch harness is open or shorted
  • Air Bag Passenger Pressure Switch circuit poor electrical connection
  • Faulty Restraint Control Module (RCM)

How to Fix the DTC B1939 Ford?

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 B1939 Ford 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 B1939 Ford code?

Need more information on how to fix the B1939 Ford code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the B1939 Ford 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 B1939 Ford Code

1. What are the common symptoms of OBDII code B1939 Ford?

The common symptoms of OBDII code B1939 Ford include the airbag warning light illuminating on the dashboard, potential loss of airbag functionality, and the possibility of related warning messages displayed on the instrument cluster.

2. What does the OBDII code B1939 Ford indicate?

The OBDII code B1939 for Ford vehicles indicates a fault in the airbag passenger pressure switch circuit due to a short to ground fault.

3. What are the possible causes of OBDII code B1939 Ford?

Possible causes of OBDII code B1939 Ford include a short to ground in the passenger pressure switch circuit, damaged wiring or connectors in the airbag system, or a faulty passenger pressure switch.

4. How serious is OBDII code B1939 Ford?

OBDII code B1939 Ford is a serious issue as it involves the airbag system, which is crucial for occupant safety in the event of a collision. It is recommended to address this issue promptly to ensure the proper functioning of the airbag system.

5. Can I drive my vehicle with OBDII code B1939 Ford?

It is not recommended to drive your vehicle with OBDII code B1939 Ford present, as the airbag system may not function correctly in the event of an accident. It is advised to have the issue diagnosed and repaired by a qualified technician before driving the vehicle.

6. How can OBDII code B1939 Ford be diagnosed?

Diagnosing OBDII code B1939 Ford typically involves using a diagnostic scanner to retrieve the code, followed by inspecting the airbag system components, wiring, and connectors for any visible damage or shorts to ground.

7. How is OBDII code B1939 Ford repaired?

Repairing OBDII code B1939 Ford may involve repairing or replacing damaged wiring, connectors, or components in the airbag system. It is recommended to follow manufacturer-specific repair procedures outlined in the service manual.

8. Can OBDII code B1939 Ford be reset without repairs?

While clearing the fault code may temporarily turn off the warning light, it is not recommended to reset OBDII code B1939 Ford without addressing the underlying issue. The fault code will likely reappear if the root cause is not fixed.

9. Are there any DIY repair tips for OBDII code B1939 Ford?

DIY repair of OBDII code B1939 Ford is not recommended due to the critical nature of the airbag system. It is best to have the issue diagnosed and repaired by a qualified automotive technician to ensure proper resolution.

10. How much does it cost to repair OBDII code B1939 Ford?

The cost of repairing OBDII code B1939 Ford can vary depending on the cause of the fault, labor rates, and parts needed for the repair. It is advisable to obtain a diagnosis and repair estimate from a reputable automotive service provider.

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