B1496 airbag control unit fault

What does error code B1496 mean in the airbag control unit?

Error code B1496 indicates an open circuit at the lid‑break sensor of the airbag system. This issue points to a disruption in the electrical connection between the sensor and the airbag control unit. As a result, the control unit can no longer monitor the sensor’s status, which triggers the airbag warning light and compromises the functionality of the affected safety circuit.

The airbag control unit is the central control module for the entire occupant protection system. It continuously processes data from various sensors to detect a crash and, in the event of an accident, precisely deploy the airbags and seatbelt pretensioners. One of its key functions is self‑diagnosis, during which all connected components—including ignition circuits and sensors—are checked for proper operation.

Error B1496 specifically refers to the “lid‑break sensor.” This sensor is designed to detect broken windows or forcibly opened doors, potentially triggering side or head airbags. An open circuit means that the signal line between this sensor and the control unit has been interrupted—whether due to a cable break, a faulty connector, or an internal fault within the sensor itself.

How do you recognize error B1496?

The primary and unmistakable symptom of error code B1496 is a permanently illuminated airbag warning light (SRS light) on the instrument panel. This warning light does not turn off after starting the vehicle, indicating an active, safety‑related malfunction in the system. Other driving functions are typically unaffected.

When reading the fault memory with an appropriate diagnostic tool, code B1496 appears as a specific entry in the airbag control unit, confirming that the fault is localized to the lid‑break sensor circuit.

In some vehicle models, a text message may also appear on the information display, alerting to an airbag system error. Limited or no communication with the airbag control unit is unusual for this particular error code, as it pertains to an external sensor circuit rather than necessarily indicating a complete failure of the unit.

Technical causes of error code B1496

The main cause of error code B1496 is typically a physical interruption in the lid‑break sensor circuit. This can result from a defective sensor itself, damaged cables or wiring due to aging or mechanical stress, or corroded or loose connectors between the sensor and the airbag control unit.

A common source of failure is damaged cables. Vibration, material aging, or improper prior repairs can cause insulation to crack or the conductor to tear, leading to the interruption detected by the control unit.

Connectors are also vulnerable. Moisture ingress can cause corrosion on the contact pins, significantly increasing electrical resistance to the point where it effectively creates an open circuit. Similarly, mechanical stress can loosen pins, preventing reliable contact.

Rarer but possible is an internal defect within the airbag control unit itself, where the input circuitry for the relevant sensor is damaged. This may also be caused by moisture or the aging of electronic components inside the unit.

Which vehicles experience error B1496?

Error code B1496 primarily occurs in various models manufactured by Mitsubishi. The Pajero, Montero, and Shogun series are particularly affected, featuring similar system architectures across multiple generations. Repair services for these specific vehicles are well established and readily available.

At Airbag24, repair services for control units exhibiting error B1496 are offered for the following Mitsubishi models:

Mitsubishi Pajero V80 (2007–2012) and V80 Facelift (2012–2021)

Mitsubishi Pajero V90 (2007–2012) and V90 Facelift (2012–2021)

Mitsubishi Montero V40

Mitsubishi Shogun V20

Mitsubishi Shogun V80

How is error B1496 repaired?

Professional repair of error B1496 begins with a thorough diagnosis of the peripheral components—cables, connectors, and the sensor itself. If the root cause lies in an internal defect within the control unit, the unit is removed and sent to Airbag24, where it undergoes component‑level analysis and restoration. This includes removing corrosion and repairing conductive traces. Finally, full functionality is rigorously tested.

First, a thorough diagnosis of the vehicle should be performed in the workshop. This includes visually inspecting all cables and connectors leading to the roof‑opening sensor, as well as conducting circuit tests (continuity and resistance measurements) between the sensor and the control unit. If necessary, the sensor itself may be temporarily replaced to rule it out as the source of the fault.

If the defect is confirmed to lie within the airbag control unit, it will be removed and sent in for repair. At Airbag24, this is followed by a detailed analysis at the circuit‑board level. Technicians examine the relevant circuits and components, correct cold solder joints, replace faulty parts, or repair conductor tracks damaged by corrosion.

Following successful refurbishment, the control unit undergoes comprehensive testing to ensure proper functionality. The repaired unit can then be reinstalled in the vehicle (plug-and-play). Finally, the vehicle’s fault memory must be cleared, after which the airbag warning light should extinguish. A 12‑month warranty is provided on the completed repair.