B1606 airbag control unit fault

What does error code B1606 mean?

Error code B1606 indicates a critical fault in the airbag control unit, specifically associated with part number B1606 in the Maserati GranCabrio M145C. The cause is either stored crash data following an accident or an internal hardware failure that results in the complete deactivation of the entire airbag system.

In such cases, the control unit locks itself for safety reasons. Its primary function—processing signals from crash sensors like pressure and acceleration sensors and triggering restraint systems—is completely disabled to prevent malfunctions.

In this specific control unit of the Maserati GranCabrio, the part number (B1606) matches the read-out error code, simplifying problem identification.

How can you recognize error B1606?

The most obvious symptom of error B1606 is a continuously illuminated airbag warning light (SRS lamp) on the instrument panel. Additionally, it is often impossible to access the airbag control unit via diagnostic equipment because communication is blocked. Consequently, the entire system is inoperative.

The SRS warning light does not turn off after starting the vehicle or flashes sporadically during driving. This is a clear indication that the passive safety system is non-functional and requires immediate inspection.

Another unmistakable sign is a failed communication attempt through the OBD interface. Workshop testers from manufacturers such as Bosch or Gutmann receive no response from the control unit, complicating diagnosis but reinforcing suspicion of an internal defect or crash lockout.

The most severe consequence is the complete deactivation of the airbag system. In the event of an accident, neither airbags nor seatbelt pretensioners will deploy, severely compromising driving safety and resulting in failure during the mandatory technical inspection.

What causes B1606?

The primary cause of error code B1606 is crash data stored in the control unit’s memory, which permanently locks the system even after minor collisions. Another common cause is internal defects in electronic components, such as integrated pressure or acceleration sensors.

After an accident—even if no airbags deployed—the control unit writes so-called crash data into its memory. These data are permanent and serve to prevent further use of the potentially damaged system, effectively locking the device irreversibly.

Internal hardware defects can also trigger the error. These include cold solder joints, damaged circuit traces, or faulty sensors directly mounted on the control unit’s circuit board. Such defects cause the system to fail self-tests and switch into safety mode.

Error B1606 rarely occurs alone. Accompanying codes such as B1000 (internal control unit error), B1600, B1615, B1622, B1632, or B1650 are often read out as well. Errors like B1806-1 (knee airbag interruption) or B1496 (open circuit) may point to peripheral issues but still require the same central examination of the control unit.

Which vehicles are affected by B1606?

Error code B1606 is highly specific and applies exclusively to the airbag control unit with the identical part number B1606. This component was installed only in the Maserati GranCabrio of the M145C series. Airbag24 specializes in repairing this particular control unit.

At Airbag24, we address this error code specifically for the following vehicle model, as both hardware and software are precisely tailored to it:

Maserati GranCabrio M145C (model years 2010–2019)

How is error B1606 professionally repaired?

Professional repair of error B1606 at Airbag24 involves targeted deletion of stored crash data along with comprehensive electronic refurbishment. Defective components, such as internal sensors on the circuit board, are replaced, followed by rigorous functional testing of the unit.

Repairs must be performed exclusively in a specialized workshop. Attempting DIY fixes using simulators or resistors is life-threatening, illegal, and results in the revocation of the vehicle’s operating license.

After sending the removed control unit to Airbag24, the repair follows a proven process. First, an initial inspection is conducted, where error codes and crash data are read out using specialized tools—even if the unit no longer communicates within the vehicle.

In the next step, stored crash data are completely and residue-free erased using dedicated software. Subsequently, electronic repairs take place, during which the circuit board is examined for damaged components, corrosion, or faulty solder joints, all of which are expertly restored.

Following successful repair, the control unit undergoes a final functional and quality inspection to ensure the flawless operation of all safety-critical systems. Airbag24 provides 2 years' statutory liability for defects on all repairs.