Airbag control unit with part number 04602420AC

What is the function of the airbag control unit 04602420AC?

The airbag control unit 04602420AC, also known as the SRS ECU (Supplemental Restraint System Electronic Control Unit), is the central control module for the occupant protection system, specifically designed for the second-generation Chrysler Intrepid. It continuously monitors sensor data and is responsible for precisely and promptly deploying airbags and seatbelt pretensioners in the event of a crash.

As the “brain” of the restraint system, this module constantly processes signals from various crash and acceleration sensors distributed throughout the vehicle. Based on this data, it assesses the severity of an impact and decides within milliseconds which safety components need to be activated.

In addition to triggering airbags and seatbelt pretensioners, the control unit also performs system diagnostics. During vehicle startup, it checks all connected components and reports any malfunctions via the airbag warning light (SRS light) on the instrument panel, ensuring safety at all times.

What types of failures occur in the airbag control unit 04602420AC?

The most common cause of failure for the 04602420AC control unit is stored crash data following an accident, which the system locks out for safety reasons. Other typical issues include internal electronic faults that result in persistent warning lights, as well as water damage or age-related component failure requiring repair.

Even after a collision—whether or not the airbags deployed—the unit stores an irreversible entry known as the “crash lock.” This locks the control unit and disables the entire airbag system until the data is professionally reset—a safety measure mandated by the manufacturer.

Internal electronic faults are also a frequent source of problems. Board-level defects, such as those affecting memory chips (EEPROM) or processors, generate diagnostic trouble codes like “Internal Error,” “B0020 – Memory Error,” or “B1035 – Internal Defect.” These hardware malfunctions prevent proper operation and necessitate component-level repairs.

External factors, such as moisture ingress, can lead to corrosion on the circuit board and short circuits. Additionally, aging of electronic components may impair the control unit’s functionality. Technically, this device is closely related to part number 04759012AI and exhibits similar fault patterns.

How do you recognize a defect in the 04602420AC control unit?

A defect in the 04602420AC control unit primarily manifests as a permanently illuminated or flashing airbag warning light (SRS light) in the cockpit. Often, the control unit can no longer be read by a diagnostic tool, or it reports error codes such as “No Communication” or “Internal Error,” indicating a severe internal malfunction.

The most obvious sign is an active SRS warning light. This light may either remain steadily illuminated immediately after starting the vehicle, or—as reported by drivers—it may illuminate after about 30 seconds or flash intermittently. In every case, this indicates a fault in the safety system, meaning the airbags will not deploy in the event of a crash.

Another clear symptom is the lack of communication with the control unit. If a workshop attempts to read the fault memory via the OBD interface, they receive no response from the module. This makes external diagnostics impossible and confirms that the issue lies directly within the control unit itself.

It is crucial to have a professional diagnosis performed before removing the control unit. A detailed inspection report from the workshop ensures that the problem truly originates with the control unit—and not with an external sensor or wiring issue—thereby avoiding unnecessary expenses.

In which vehicles is the 04602420AC installed?

The airbag control unit with part number 04602420AC is primarily installed in the second-generation Chrysler Intrepid (model years 1997–2004). Due to platform similarities, it may also be used in related models such as the second-generation Dodge Intrepid.

At Airbag24, we repair both the 04602420AC control unit and its compatible counterpart, part number 04759012AI, for the following specific vehicle models:

Chrysler Intrepid (second generation, 1997–2004)

Professional restoration restores full functionality to the safety system in these vehicles and provides a reliable, cost-effective alternative to expensive new parts.

How is the 04602420AC control unit professionally repaired?

Professional repair of the 04602420AC at Airbag24 includes a thorough initial inspection to analyze error codes and hardware defects. Subsequently, stored crash data is erased, defective electronic components on the circuit board are replaced, and internal memory errors are corrected, followed by a final functional test to ensure full operational readiness.

After you send the removed control unit to Airbag24, the repair process begins with a thorough analysis. Our technicians read out stored fault codes and inspect the hardware on the circuit board to pinpoint the exact cause of the defect—whether it’s a locked memory chip due to crash data or a faulty component.

The next step is the actual restoration. Stored crash data is reset at the hardware level, and defective electronic components such as processors or memory modules are replaced with new, specification‑compliant parts. Finally, a comprehensive functional test is performed to ensure the unit communicates fully and is ready for operation.

This process restores the control unit to factory‑ready condition, allowing it to be reinstalled in the vehicle without additional programming (plug-and-play). We provide 2 years' statutory liability for defects on every repair performed.