Airbag control unit with part number 77960-TGH-A01

What is the function of the airbag control unit 77960-TGH-A01?

The airbag control unit with part number 77960-TGH-A01 is the central control module for the occupant restraint system (SRS) in 10th-generation Honda Civic models, including the Type R. It analyzes data from acceleration and seatbelt force sensors and, within milliseconds, determines whether to deploy airbags and tighten seatbelts to protect occupants during a collision.

This device, also known as the Airbag Control Unit (ACU), serves as the brain of the entire safety system. It maintains constant communication with all relevant vehicle sensors to ensure continuous monitoring and operational readiness.

In the event of a collision, it processes incoming signals and activates the appropriate restraint devices. Additionally, it stores critical system data and fault codes that are essential for diagnostics and, following a crash, for retrieving crash data.

Why does the airbag control unit 77960-TGH-A01 fail?

The most common cause of failure for the 77960-TGH-A01 control unit is the retention of crash data in its internal memory (EEPROM/Flash) after an accident. Other causes include internal hardware defects on the circuit board, such as faulty components (ICs, drivers), cold solder joints, or issues with the internal power supply that lead to communication failures.

Following even a minor impact, the control unit locks out SRS functions and stores so‑called crash data. These data typically cannot be erased using standard diagnostic tools, making the unit appear unusable—even though it may still be fully functional electronically.

Another significant source of failure is internal electronic malfunctions. This includes the breakdown of specific components on the circuit board, such as memory chips (EEPROM), voltage regulators, or driver ICs. Thermally induced cold solder joints can also result in intermittent or permanent communication problems with the diagnostic tester.

Generic error codes like “internal control unit error” (e.g., B1015) likewise indicate a hardware defect within the module. Such errors cannot be resolved simply by clearing them and require component‑level repair.

How do you recognize a fault in the 77960-TGH-A01 control unit?

A malfunctioning 77960-TGH-A01 control unit primarily manifests as a continuously illuminated airbag or SRS warning light on the instrument panel. Often, the control unit becomes unresponsive to diagnostic equipment (no communication), or the fault memory contains persistent error codes that cannot be cleared, even after the underlying issue has been fixed.

The clearest indication is the active SRS warning light, which remains on even after restarting the engine. This signals a problem within the restraint system, often originating in the control unit itself.

In the workshop, the issue frequently appears when the diagnostic tool fails to establish communication with the airbag control unit. An error message such as “No communication with airbag control unit” emerges, further complicating diagnosis.

Even if communication is temporarily restored, error codes like “crash data stored” or “internal control unit error” may persist in memory. These faults resist attempts at deletion and effectively disable the entire SRS system.

In rarer cases, sporadic malfunctions occur, where the SRS indicator lights up only under certain temperature conditions or other comfort features are affected. This often points to defective solder joints on the circuit board.

In which vehicles is the 77960-TGH-A01 control unit installed?

The airbag control unit 77960-TGH-A01 is specifically used in Honda vehicles. At Airbag24, we repair this module for the 10th‑generation Honda Civic, manufactured roughly between 2015 and 2022—including the sporty Honda Civic Type R variant.

Our repair expertise covers the entire 10th‑generation Honda Civic lineup. Specifically, this includes:

- 10th‑generation Honda Civic (circa 2015–2022)

- Honda Civic Type R (based on the 10th generation)

How does Airbag24 repair the 77960-TGH-A01?

Repair begins with the professional removal of the control unit in a workshop. After sending it to Airbag24, the unit undergoes analysis on a test bench, crash data is cleared, and any electronic hardware defects on the circuit board are rectified. Following a successful final test, the refurbished original part is returned without requiring re‑coding in the vehicle.

First, a specialized workshop should verify the fault to rule out issues with the wiring harness or sensors. Subsequently, the control unit is removed in compliance with safety regulations (disconnect the battery and observe the required waiting period).

Upon receipt at Airbag24, the module undergoes a comprehensive technical inspection. Our technicians read out the fault memory and analyze the hardware for defects.

The actual repair involves safely erasing the stored crash data and repairing the electronics. Defective components such as ICs, memory chips, or solder joints are professionally replaced or reworked, restoring the device to its pre-accident condition.

A final functional test ensures that the control unit communicates flawlessly again and all internal faults have been resolved. We provide 2 years' statutory liability for defects on the completed repair.