B2212: Occupant Module Internal Fault

Hardware fault

What B2212 means

The occupant classification module runs internal checks every time it powers up, verifying memory, its processing, and the circuits it uses to read the seat sensors. B2212 is stored when one of those checks does not pass. At that point the module considers its own output unreliable and the restraint system loses its occupant classification input.

There is no connector to reseat with this one. The fault is inside the module housing, which is why a shop can test the seat sensors and their wiring, find everything within spec, and still have the code present. Before writing the module off, confirm that the supply voltage and grounds feeding it are solid, since a module running on poor power can fail a check it would otherwise pass.

Common causes

• Age related failure of a component inside the module
• Moisture reaching the module from a wet carpet or a leak in the floor area
• A voltage spike from jump starting, welding, or a failing charging system
• Physical damage during seat removal or interior work
• A used module installed that was already faulty when it was pulled

Crash data or hardware fault?

Hardware means the module itself is what failed, separate from any wiring measurement and separate from crash data. Crash data is the permanent deployment record in the airbag module, written when the restraints fire and unreachable by a scan tool. B2212 describes an internal condition the module found on its own.

Does our reset clear it?

When B2212 is stored rather than live, a mail-in reset can clear the fault memory and return the module to a ready state. When the internal failure is ongoing, the module writes the code again on its first self test and needs to be replaced instead. We are straight with customers about which situation a module is in when it reaches our bench.

Which makes throw it

Chrysler is the make listed for B2212 in our lookup, on vehicles using an occupant classification module for the passenger seat.

What to do next

Check battery voltage and the module's power and ground circuits before condemning the unit, since a module reading low voltage can fail its own self test without being defective. Look for water under the carpet near the module as well. If the vehicle side is clean, call 501-988-0611 and we will tell you whether a reset or a replacement OEM module is the right next move. Related codes: B2207, B1B00, 43-2X.