Diagnostic trouble code (DTC) information SRS-021D

Condition 

Fig 1: Identifying Front Right Front Impact Sensor

Courtesy of VOLVO CARS OF NORTH AMERICA.

The Supplemental Restraint System Module (SRS) checks the signal from the front left front impact sensor.

Diagnostic trouble code (DTC) SRS-021D is stored if the Supplemental Restraint System Module (SRS) registers that the signal cable is cross-connected

The diagnostic trouble code (DTC) can only be diagnosed when the ignition is switched on (12 V). In other words, the diagnostic trouble code (DTC) can only be diagnosed when the ignition is switched from position 0 to positions I, II or III.

Substitute Value 

• None.

Possible Source 

• Incorrect connection of the signal cables between the front left front impact sensor and the Supplemental Restraint System Module (SRS). The signal cables are reversed between the two terminal pins in the side impact sensor or in the Supplemental Restraint System Module (SRS)
• Incorrect repair of SRS wiring. The signal cables to the two terminal pins on the front impact sensor have been reversed.

Fault symptom[s] 

• The SRS indicator lamp is lit.