Airbag DM Fault Code 99

Airbag DM Fault Code 99

Rapid continuous flashing of the airbag warning light - Both front crash sensors disconnected.

Normal Operation

Each crash sensor has three wires. Two deploy the airbag and monitor the sensors connection to the diagnostic monitor. The third wire monitors the mounting of the sensor to the vehicle bodywork. A code 99 is declared if both sensors are disconnected and not properly grounded.

Fault Analysis

1. Disarm the airbag system and fit airbag simulators (6.4.21.4).
2. Check continuity of all circuits listed below and service as necessary.

Also check for correct grounding of the diagnostic module and the sensor cases.

3. Reconnect all connectors, clear fault code 99. Switch off the ignition and then switch on again. Check that the airbag warning lamp comes on at 'ignition on' and extinguishes after approximately six seconds on satisfactory completion of the airbag system self-check.
4. Rearm the airbags (6.4.21.4).