Airbag control unit with part number 16020402

What is the function of Airbag Control Unit 16020402?

The airbag control unit with part number 16020402, often also listed as 16020402GD, is the central control module for the occupant safety system (SRS) in the Daewoo Kalos T250. It processes signals from crash sensors and, in the event of a collision, controls the deployment of airbags and seatbelt pretensioners.

As the “brain” of the passive safety system, this module continuously monitors and evaluates data from the acceleration sensors. If it detects a collision exceeding predefined thresholds, it sends ignition pulses to the appropriate restraint systems within milliseconds.

In addition, the control unit 16020402 communicates with other vehicle systems and stores relevant system states and fault codes in its internal memory, which can be read out via a diagnostic interface.

Why does control unit 16020402 fail?

A failure of control unit 16020402 is often caused by the storage of crash data in the internal EEPROM after an accident or by electronic defects on the circuit board. These include faulty SMD components, cold solder joints, or damaged traces.

One of the most common causes of apparent total failure is the permanent retention of crash data. After a triggering event—even minor collisions—the control unit electronically locks itself to prevent unintended further deployments. This condition cannot be resolved simply by clearing the fault memory; it requires intervention in the EEPROM memory.

Furthermore, purely electronic faults can impair functionality. Over time, vibrations and thermal stress may lead to cold solder joints or the failure of individual SMD components (Surface-Mounted Devices) on the circuit board. Corrosion caused by moisture ingress or issues with connector contacts are also well-known sources of failure.

How do you recognize a defect in control unit 16020402?

A defect in control unit 16020402 primarily manifests as a permanently illuminated SRS airbag warning light in the instrument cluster. Additionally, specific fault codes such as “control unit defective” or the frequently cited code B1111 in forums are stored in the fault memory.

The most noticeable symptom is the persistently lit airbag warning lamp that fails to extinguish after starting the vehicle. This indicates a serious malfunction in the restraint system, compromising the proper functioning of airbags and seatbelt pretensioners.

During diagnosis using an appropriate workshop tester, fault codes can often be retrieved that directly point to an internal fault in the control unit. Typical messages include “control unit defective,” “internal error,” or specific codes like B1111.

It’s important to note that a lit SRS lamp can also result from external components, such as defective seat occupancy mats, seatbelt pretensioners, under-seat connectors, or the clock spring in the steering wheel. A thorough diagnosis before removing the control unit is therefore essential.

In which models is 16020402 installed?

The airbag control unit with part number 16020402, or alternatively designated 16020402GD, was specifically developed for the Daewoo Kalos of the T250 series. Repair is intended exclusively for this particular vehicle model.

At Airbag24, we repair control unit 16020402 for the following vehicle model. Please ensure that the part number on your unit matches those listed here:

Daewoo: Kalos T250 (model years 2002–2011)

How does the repair process work at Airbag24?

The repair process begins with the professional removal of the control unit and its shipment to Airbag24. Our technicians perform an electronic repair, erase crash data from memory, and restore full functionality before returning the tested unit.

First, fault codes should be read out and documented in the vehicle. Next, the vehicle battery must be disconnected, and a waiting period observed, before the control unit is carefully removed. Due to safety considerations, these tasks should only be carried out by qualified personnel.

Upon receipt at Airbag24, a detailed analysis of the circuit board is performed. Depending on the cause of the fault, defective components are replaced, solder joints are reworked, or crash data stored in the EEPROM is erased, restoring the device to factory settings. Mechanically destroyed or thermally damaged units are excluded from repair.

Following successful restoration and a functional test, the control unit is returned to you. Reinstallation should also be performed by a specialized workshop, which will finally clear the fault memory and verify the correct operation of the entire SRS system. We provide 2 years' statutory liability for defects on all repairs.