Drivers first notice the airbag/occupant‑protection light staying on after a cold start or flashing briefly during ignition. The warning lamp may remain solid for the entire drive cycle, but power‑train operation, braking, steering, and other vehicle functions continue normally. Because the fault is confined to the supplemental restraint system (SRS), there is no loss of engine power, fuel economy, or emissions‑related performance.
The airbag control module contains a regulator that keeps the B‑circuit voltage within a tight 5 V‑12 V window. Moisture intrusion, corrosion, or age‑related board degradation can cause the regulator to output a higher voltage, triggering P2260.
A damaged harness, chafed insulation, or a pinched connector can create a low‑impedance path from the vehicle’s 12 V battery to the B‑circuit. The resulting over‑voltage is interpreted as a fault and lights the SRS indicator.
Corroded pins or a loose ground strap can cause the module to read a phantom high voltage. Even a marginal increase of 0.5 V above the calibrated range can set the P2260 code.
The module’s software stores calibration data for the B‑circuit. A failed flash write, improper re‑programming, or exposure to electromagnetic interference can corrupt this data, making the module think the circuit is high.
Installation of non‑OEM accessories that draw power from the same harness (e.g., aftermarket alarms, infotainment upgrades) can introduce voltage spikes that the SRS module interprets as a high‑circuit condition.
– Connect the tool, read all stored SRS codes, and note any additional faults (e.g., P2261, P2262).
– Measure the battery while the engine is off; it should be 12.4 V ± 0.2 V. Extreme low or high battery voltage can cause false readings.
– Visually check for frayed wires, burnt insulation, or loose pins.
– Use a multimeter to measure resistance from the B‑circuit pin to ground; it should be >10 kΩ. Anything lower indicates a short.
– With the ignition “ON” (engine not running), probe the B‑circuit terminal. Voltage above 12 V (or the manufacturer‑specified limit) confirms a high‑circuit condition.
– Using the scan tool, execute a “Bidirectional Control” or “Module Test” for the airbag control unit. Failure to communicate suggests internal damage.
– Erase the P2260, then cycle the ignition three times. If the lamp returns, the fault persists.
– If wiring is at fault: repair or replace the damaged harness section, clean connectors, and re‑torque fasteners.
– If the module voltage regulator is suspect: many technicians find that internal repairs are temporary; a replacement module provides a permanent solution.
– Install a VIN‑matched airbag control unit. Use the manufacturer’s re‑programming software to load the correct calibration and immobilizer data.
– Re‑scan for codes, perform a functional SRS test (often a “Self‑Check” mode), and confirm the warning lamp is extinguished.
Typical costs
Because the airbag control module integrates safety‑critical functions such as crash detection, occupant classification, and immobilizer communication, a single internal fault can compromise the entire system. While wiring repairs may address the symptom, the underlying regulator or flash‑memory failure often recurs.
Flagship One specializes in VIN‑matched control modules, providing a plug‑and‑drive solution backed by a warranty. Modern control modules are complex and integrated with security and immobilizer systems. That’s why choosing a replacement isn’t only about the hardware—it’s about correct programming and compatibility. Flagship One supplies pre‑programmed units that match your vehicle’s VIN, ensuring seamless integration and reliable operation.
Service Recommendation: Most issues related to this fault are diagnosed and corrected through inspection, wiring repair, and calibration rather than module replacement. For modules not typically replaced through aftermarket suppliers, diagnosis and repair should be performed by a certified automotive technician with access to factory service information and tooling.