B1044: Driver Airbag Squib Coding Fault

Hardware fault

What B1044 means

Mercedes restraint modules are coded to the vehicle. That coding tells the module what hardware is present on each circuit, which airbag variant is fitted, and what parameters to expect. B1044 means the coding record for driver airbag squib 1 is faulty, missing, or inconsistent with the rest of the configuration, so the module will not commit to arming that circuit.

This most often follows a parts swap or a programming session. A control unit taken from another vehicle carries that vehicle coding. A module that lost power during a variant coding write can end up with a half finished record. In either case the wiring can be perfect and the airbag can be the correct part while the code still stands.

Common causes

• A used restraint control unit installed without being coded to this vehicle
• A variant coding session interrupted by low voltage or a lost tool connection
• Coding that does not match the airbag configuration actually fitted to the car
• A driver airbag variant installed that the module was never coded to expect
• Corrupted configuration memory inside the control unit
• A previous repair that wrote coding from the wrong model or equipment level

Crash data or hardware fault?

B1044 lands in the hardware group because it describes the module internal state rather than a resistance reading on a wire. It is live in the sense that the module reports it on every power up while the coding is wrong. Crash data is a separate thing entirely: a permanent deployment record that no coding procedure touches and that only a module reset clears.

Does our reset clear it?

A reset erases stored faults and crash data, and on a coding complaint that may not be enough by itself. The module still needs correct variant coding for this vehicle before it will accept the driver squib circuit. When we reset a Mercedes restraint module we return it cleared of stored faults, and the coding side is handled with a capable scan tool on the car. Call 501-988-0611 if you want to talk through which part of that applies to your situation.

Which makes throw it

This is a Mercedes-Benz code, and the coding concept behind it is specific to how Mercedes configures restraint control units. Other makes handle configuration differently, so the same number on another vehicle will not mean the same thing.

What to do next

Find out whether the control unit or the driver airbag was recently replaced, because that answer usually solves the case before any testing begins. Read the current coding and compare it against the vehicle data card or equipment list. Recode the unit with a stable power supply on the battery and a tool connection that will not drop. If the code persists after correct coding, the control unit itself is suspect, and we supply genuine OEM Mercedes airbag modules. Related codes: B1035, B1052, B1B72.