Airbag Control Module Internal Failure
Diagnostic trouble code B1924 indicates an internal fault within the Restraint Control Module (RCM) or a system disarm condition. This Ford-specific code sets when the RCM detects an anomaly during its self-diagnostic routines, such as a failure in the airbag ignition voltage monitoring circuit, an EEPROM memory error, or when the system has been intentionally or fault-induced disarmed. The RCM continuously monitors the integrity of its internal firing circuits and impact sensors; if it detects an inconsistency that could prevent proper airbag deployment, it stores this code and may disable the passive safety system to prevent accidental deployment.
1. Commonly Affected Makes
2. Most Common Causes
- Internal failure of the Restraint Control Module (RCM)
- Low voltage or voltage drop in the RCM power supply circuit
- EEPROM memory failure within the airbag module
- System disarm due to incomplete previous service procedure
- Water damage or corrosion at the RCM connector
- Failure in the airbag ignition voltage monitoring circuit
- Windshield replacement or structural repair without RCM recalibration
- Electromagnetic interference or electrostatic discharge damage to the module
3. Symptoms You Will Notice
- Airbag warning light illuminated on the dashboard
- Supplemental Restraint System (SRS) disabled or inoperative
4. Step-by-Step Diagnosis
Scan the RCM for fault codes and record all stored codes.
Check the RCM power and ground circuits for proper voltage and continuity.
Inspect the RCM connector for corrosion, bent pins, or water intrusion.
Verify that no previous service procedures (e.g., airbag replacement) were left incomplete.
If all checks pass, suspect internal RCM failure and replace the module.
5. Frequently Asked Questions
Is it safe to drive?▼
No, it is not safe to drive because the airbag system may be disabled, increasing the risk of injury in a collision. Have the vehicle towed to a repair facility.
How much does it cost to fix?▼
Repair costs typically range from $200 to $1,200 USD, depending on whether the RCM needs replacement and if programming is required.