Airbag control unit with part number 985P15DC0A

What is the Airbag Control Unit 985P15DC0A?

The airbag control unit with part number 985P15DC0A is the central processing unit of the Supplemental Restraint System (SRS) in the Infiniti QX30 and Q30 models of the H15 series. It analyzes data from crash and G‑sensors to precisely deploy airbags and seatbelt pretensioners in the event of a collision, while continuously monitoring the entire system.

As the “brain” of the passive safety system, this control unit constantly evaluates signals from acceleration sensors, seatbelt buckles, and seatbelt tensioners to provide optimal protection for occupants in an emergency. It ensures the proper functioning of all restraint devices.

If the control unit fails, the entire airbag system is typically disabled. This is indicated by the SRS warning light on the instrument panel and constitutes a significant safety deficiency that may be flagged during vehicle inspections.

What Defects Occur in 985P15DC0A?

The most common cause of malfunction in the 985P15DC0A control unit is the storage of crash data after an accident, which locks the device. Other causes include internal electronic faults such as memory errors or power supply issues. Overvoltage or moisture can also lead to complete failure.

Following a collision, the unit permanently stores crash events in its internal memory (EEPROM/Flash), preventing further operation. This is a manufacturer‑specified safety feature requiring professional repair. The error code B1000 often indicates this problem.

In addition to crash‑lockout, components on the circuit board may fail. Defective semiconductors, voltage regulators, broken solder joints, or other SMD parts can result in communication failures or internal error messages—even without an actual crash.

This control unit is also known under the alternative part numbers 985H15DC0A, 985P05DC0A, and 985155DC0A. The fault patterns and electronic repair procedures are identical across these variants.

How Do You Recognize a Fault in 985P15DC0A?

A defect in the 985P15DC0A airbag control unit primarily manifests as a continuously illuminated or flashing SRS/Airbag warning light on the dashboard. Often, communication with the control unit via an OBD diagnostic tool becomes impossible, or specific internal error codes such as B1000 are stored.

The illuminated warning light is the clearest indication that the airbag system is not operational. The vehicle is signaling a serious malfunction in the passive safety system that should be promptly inspected by a qualified workshop.

Another clear symptom is when the workshop’s diagnostic tool cannot access the airbag control unit. The module no longer responds to queries, preventing accurate fault analysis through the OBD interface.

Thorough diagnosis is essential. Before removing the control unit, external sources of failure—such as defective sensors, seatbelt pretensioners, loose connectors, or damaged wiring harnesses—must be ruled out, as they can produce similar symptoms.

In Which Models Is 985P15DC0A Installed?

The 985P15DC0A airbag control unit is specifically used in Infiniti vehicles. At Airbag24, this part number is offered for professional repair in Infiniti QX30 and Q30 models of the H15 series manufactured between 2016 and 2020.

Specifically, this control unit is intended for the following vehicle series:

Infiniti: QX30 (H15 series, model years approx. 2016–2020), Q30 (H15 series, model years approx. 2016–2020)

How Is 985P15DC0A Professionally Repaired?

Repair of the 985P15DC0A control unit at Airbag24 includes professionally erasing stored crash data and fixing internal electronic faults. Upon receipt, the unit is thoroughly inspected, its memory reset to factory settings, and any defective components replaced to ensure plug-and-play functionality.

After receiving the removed control unit at Airbag24, a comprehensive analysis is performed on a specialized test bench. Here, communication protocols and stored fault data are read to determine the exact cause of the defect.

The core of the repair involves accessing the internal memory chip (EEPROM/Flash). Technicians erase crash data (crash reset) and restore the unit to its pre‑accident state, while correcting any corrupted data records.

If hardware defects are responsible, faulty components such as voltage regulators or driver ICs on the circuit board are expertly replaced. A final functional test confirms that the unit operates flawlessly once again.

Since the original control unit is repaired, vehicle-specific data such as the Vehicle Identification Number (VIN) and coding remain intact. This allows for easy plug-and-play installation without additional programming. All repairs come with 2 years' statutory liability for defects.