Airbag control unit with part number 4672602AB

What is the function of Airbag Control Unit 4672602AB?

The airbag control unit with part number 4672602AB is the central control module of the passive safety system (SRS) in the Dodge Caliber. It continuously analyzes data from crash sensors to precisely and millisecond‑fast deploy the airbags and seatbelt pretensioners in the event of a collision, while also monitoring the entire system for proper functionality.

As the “brain” of the restraint system, this control unit is specifically configured for the vehicle architecture of the Dodge Caliber PM model years 2006–2009, as well as the facelifted model from 2009 to 2011. It collects and processes information from various acceleration and pressure sensors distributed throughout the vehicle.

Based on this data, the control unit determines whether a crash has occurred and which restraint devices—such as front or side airbags—need to be activated. After deployment, it stores relevant crash data, an important feature for accident analysis but also potentially causing a system‑wide lockout.

Why does Airbag Control Unit 4672602AB fail?

A failure of control unit 4672602AB is most commonly caused by stored crash data following an accident, which can block further system operation. Other causes include internal electronic defects on the circuit board, damage due to overvoltage, or issues with the power supply that may lead to complete system failure.

The most frequent cause of malfunction is the storage of crash data. After a collision, the control unit locks itself for safety reasons and must be professionally reset. This is an intentional feature, not a software bug. Without a so‑called “crash reset,” the airbag warning light remains illuminated and the system becomes inoperable.

Internal hardware defects are another common source of failure. These include faulty components such as capacitors, processors, or memory chips on the circuit board. Error codes like B1111 (“control unit defective”) or 65535 often indicate such internal hardware damage requiring expert repair.

Problems with the power supply—whether due to insufficient onboard voltage or voltage spikes (overvoltage)—can damage sensitive electronic components inside the control unit. This may result in sporadic failures, especially under heat, or even total loss of communication.

Various equivalent or compatible part numbers exist for this control unit, which can be installed in the same vehicles. These include: 68148034AA, 4896616AA, 4896616AB, P56054203AF, P04896621AE, and P04672603AE.

How do you recognize a defect in 4672602AB?

A defect in control unit 4672602AB typically manifests as a permanently lit or flashing airbag warning light (SRS light) in the instrument cluster. Additional signs include lack of communication with diagnostic equipment or specific error codes indicating an internal control unit fault.

The clearest symptom is the active SRS warning light. If it stays on after starting the engine, the system signals a critical error. In this state, airbags and seatbelt pretensioners are disabled, posing a significant safety risk and requiring immediate inspection at a workshop.

Often, diagnostic equipment cannot establish communication with the airbag control unit. This complete communication failure makes further troubleshooting of sensors or wiring impossible, clearly isolating the fault to the control unit itself.

When reading out error codes, specific entries such as “B1111 – control unit defective,” “65535 – internal error,” or manufacturer‑specific codes like “93F9” directly point to an internal hardware defect. CAN bus errors or messages about faulty supply voltage may also trace back to the control unit.

In which vehicles is control unit 4672602AB installed?

The airbag control unit with part number 4672602AB was specifically developed for models manufactured by Dodge. At Airbag24, we primarily service this component across the entire Dodge Caliber lineup, including both pre‑facelift and facelift models.

At Airbag24, we repair part number 4672602AB and its equivalent variants for the following specific vehicle models:

Dodge Caliber PM (model years 2006–2009)

Dodge Caliber PM Facelift (model years 2009–2011)

How does the repair of 4672602AB proceed at Airbag24?

After sending the removed control unit to Airbag24, experienced technicians perform a professional analysis. The repair includes fixing electronic defects on the circuit board and resetting stored crash data. The unit is then thoroughly tested and returned fully functional, backed by 2 years' statutory liability for defects.

The process begins with the proper removal of the control unit. In the Dodge Caliber, it is often located beneath the center console, in the glove compartment, or under the seats. Before removal, be sure to disconnect the vehicle battery for at least 10–30 minutes to prevent accidental airbag deployment.

Upon arrival at Airbag24, the control unit undergoes a thorough inspection. Using specialized diagnostic and analysis tools, technicians pinpoint the exact source of the fault—whether it’s a defect on the circuit board, a damaged component, or data corruption caused by crash events.

The subsequent repair is performed at the component level. Defective parts are replaced, and cold solder joints are reworked. Stored crash data is completely and irreversibly erased via an electronic reset. The control unit is then fully functional again, without requiring any new vehicle coding.

Following successful restoration, each control unit undergoes a final test to ensure flawless operation of all systems. You receive a component that performs just like a brand-new part, backed by 2 years’ statutory liability for defects on the repair performed.