Generic fault code

B0073 — Second row left seat belt pretensioner deployment control: malfunction

Q: What usually causes code B0073?

Damaged, chafed or pinched wiring. The most likely causes come first. Only a check on the car confirms which one is yours.

Q: What are the symptoms of code B0073?

Airbag warning light on. The airbag or pretensioner involved may not deploy in a crash. Sometimes a seat belt warning. These are the usual symptoms of this kind of fault: not all of them always appear, and sometimes you notice nothing.

The control unit stores code B0073 when it detects this fault: “Second row left seat belt pretensioner deployment control: malfunction”.

Indicative severity: CriticalRestraint systems (airbags and pretensioners)

Updated on October 13, 2026

Reviewed by Daniel Morales, founder of Reprorace SL, on October 13, 2026

What does code B0073 mean?

Airbags and seat-belt pretensioners. With a fault here they may not deploy in a crash.

System: B · Body
Area: Restraint systems (airbags and pretensioners) · Car system: Airbags and passive safety
Type: Generic (SAE J2012 / ISO 15031-6): the same meaning on every make
Indicative severity: Critical. Stop the vehicle safely and do not use it until repaired (restraints, high voltage).

What usually causes code B0073?

Damaged, chafed or pinched wiring

The most likely causes come first. Only a check on the car confirms which one is yours.

What are the symptoms of code B0073?

Airbag warning light on
The airbag or pretensioner involved may not deploy in a crash
Sometimes a seat belt warning

These are the usual symptoms of this kind of fault: not all of them always appear, and sometimes you notice nothing.

Can I keep driving with code B0073?

No. Stop the vehicle somewhere safe and do not use it until a professional has checked it: the fault affects the restraint systems (airbags and pretensioners) or the high-voltage system. Call roadside assistance.

This is guidance only: only someone who checks the car can say whether it is safe to drive.

An indicative description of the code's generic meaning. Each manufacturer may give it a different meaning, conditions or tests: always follow its service information and your workshop's advice.

What you can do yourself

For this kind of fault

Do not measure or tamper with airbag circuits, and do not unplug connectors under the seats with the ignition on. Book a workshop as soon as possible.

Read the code and keep the report: with an ECO-LITE in the OBD socket you see it on your phone or computer, with the data captured when the fault happened.
Do not touch anything in this system: no airbag connectors or connectors under the seats, no orange cables or high-voltage parts. Only a professional with the right training and equipment should check them.
Do not clear the code to switch off the warning light: the fault is still there and the workshop needs the stored data.
Do not use the car until it has been checked: call roadside assistance or book the workshop, and take the report with you.

Read your car's fault codes on your phone

With an ECO-LITE in the OBD socket you see the codes in your account, with the data captured when the fault happened, and your workshop can check them remotely, always with your permission.

See the ECO-LITE Reserve (presale)

Related codes

B0058Third row right seat belt sensor: malfunction
B0071First row center seat belt pretensioner deployment control: malfunction
B0072Passenger seat belt pretensioner A deployment control: malfunction
B0075Second row right seat belt pretensioner deployment control: malfunction
B0078Third row right seat belt pretensioner deployment control: malfunction
B0079Driver seat belt pretensioner B deployment control: malfunction

B00xx codes: airbags, pretensioners and seat belts

All fault codes