B48 is the Mercedes sensor that tells the restraint system whether the front passenger seat is occupied and whether a child seat is present. B106C reports that the control unit has lost a clean connection to it.
The passenger occupancy and child seat recognition system decides whether the passenger airbag should be enabled, suppressed, or deployed at reduced force. B48 provides that input. When the restraint control unit stops receiving valid messages from it, or detects a cable problem on the circuit, B106C is stored and the passenger side protection strategy is compromised.
The definition covers both communication and cable faults, which matters for diagnosis because it means the fault might be in the mat, the connector, the harness, or the flow of data itself. Since the sensor lives in the passenger seat cushion and its wiring exits under the seat, seat service and floor moisture are the two things that disturb it most.
Live circuit and communication behavior is what this code tracks, which puts it with the circuit codes. The control unit rechecks the link constantly and the code follows what the wiring and the sensor are actually doing. Crash data is the contrasting case: a single permanent entry written at deployment that stays until a module reset takes it out.
The reset does not restore a lost sensor connection. Repair the harness or replace the occupancy sensor, then confirm the control unit sees it again. Mail in reset service comes into play when that same Mercedes control unit is holding crash data from a deployment, which a scan tool cannot erase no matter how many times it is asked.
Mercedes-Benz uses B106C and the B48 designator for front passenger seat occupied and child seat recognition. Different models carry different versions of this system, so confirm which hardware the car has before ordering a sensor.
Slide the passenger seat through its travel and check whether the code comes and goes, since that behavior points straight at the flex harness under the seat. Unplug the connector and inspect both halves for corrosion and spread terminals. Verify the sensor has power and ground. If the mat inside the cushion is damaged, the sensor assembly needs replacing, and we can help identify the right genuine OEM part at 501-988-0611. Related codes: B1064, B106F, B1057.
Trace the wiring and connectors first. If the module still holds the fault after the repair, mail it to us and we will clear it.
Genuine OEM, tested, and shipped ground from Jacksonville, Arkansas.
Do not see it listed? Request a part or call 501-988-0611.