Diagnostic Modes
During normal operation, the control unit operates in the fault alarm mode. After the ignition is switched on, the airbag warning light comes on for 7 seconds and then goes out. This indicates that there are no faults.
After 7 seconds, the malfunction indicator starts flashing at a frequency of 1 Hz, a malfunction has been detected in the system. If the warning light stays on continuously for more than 7 seconds, then this indicates either a malfunction of the system or an airbag deployment that has occurred. If the signaling device does not light up after turning on the ignition, then this indicates a short circuit or an open in the signaling device or control unit circuit.
The control unit in a system with a single airbag does not have additional self-diagnosis capabilities.
In a system with two airbags, you can put the control unit in diagnostic mode. To do this, turn off the ignition, open the driver's door, turn on the ignition, and press the door switch at least 5 times within 7 seconds after turning on the ignition.
After that, the signaling device will either flash periodically (no fault), or will start issuing a fault code in the form of a sequence of short flashes, as shown in the figure.
After repairing the system, turn the ignition off, then back on and press the driver's door switch at least 5 times within 7 seconds after the ignition is turned on. The control unit will go into fault alarm mode.
Fault code (number of flashes) | Decryption |
0 | Fault not found |
2 | Faulty driver airbag module circuit |
7 | Faulty control unit |
8 | Faulty passenger air bag module circuit |