93C2

What the Code Means

Code 93C2 flags a fault in the passenger presence sensor (OC3 circuit) — the mat built into the front passenger seat cushion, or its wiring. The SRS module detects an open circuit or out-of-range resistance in the mat circuit. As a result, the control module can't reliably tell whether the passenger seat is occupied and disables front passenger airbag deployment.

On E90 bodies this is a common problem: the mat wears out over time, and the connector under the seat corrodes from moisture and temperature swings.

Symptoms

• Airbag warning light on the instrument cluster;
• front passenger airbag deactivated;
• code 93C2 stored in the airbag module.

Diagnosis and Repair

1. Read fault codes with ISTA or INPA and confirm 93C2 is present in the airbag module.
2. Inspect the passenger presence sensor connector under the passenger seat: check for corrosion, damaged contacts, and wiring condition.
3. If the connector and wiring are fine but the fault returns after clearing, replace the seat occupancy mat (OEM 65779257613).
4. After the repair, clear the codes and reset the airbag module.

Secondary Problems

• In a crash, the front passenger airbag may not deploy — the risk of injury to the passenger goes up;
• the airbag light stays on, which causes a failed MOT.

Don't put off the repair: the fault directly affects the passive safety system.