Works like a charm!
Mercedes-Benz A-Class V177 Saloon airbag control unit repair
Mercedes-Benz A-Class V177 Saloon airbag control unit repair at Airbag24
Airbag24 repairs defective airbag control units professionally and affordably. Both private customers and workshops can order without registration and benefit from fast processing, 2 years' statutory liability for defects and plug&play installation.
Airbag24 works with state-of-the-art diagnostic technology and specialised repair processes. Because defective control units often involve only individual components, a professional overhaul can be considerably cheaper than buying new.
Our advantages: no registration required, a direct online ordering process for B2B and B2C customers, express shipping and comprehensive quality testing. The repaired control unit works like a new part.
Notes
Mounting position
Repair type
Which repair matches your fault code?incl. VAT plus shipping
Not sure? Just send us an enquiry or give us a call — we're happy to advise you.
4.8Google reviews of our shop(233)
Secure payment with
Matching part numbers
Your part number isn't listed? The list isn't complete – we can usually repair it anyway. Simply create a repair order, or ask us first.
Repair time
Our estimated repair time for this product is about: 3–4 business days
Which repair matches your fault code?
Below your code you can see what needs to be done.
Your error code isn't listed? The list isn't complete – we can usually repair it anyway. Simply create a repair order, or ask us first.
Specifications
- Make
- Mercedes-Benz
- Model
- Mercedes-Benz A-Class
- Series
- V177 Saloon (2018-2025)
Shipping & repair from Germany
Airbag24 repairs your component in Berlin — usually within 3–4 working days.
Standard shipping within Germany is free; we normally return your part by UPS.
You pay for and insure the inbound shipment to us. On explicit request we ship by express — the extra cost is borne by the customer.
If you withdraw from the contract, you bear the cost of returning the item.
Google reviews
4.8Based on 233 reviewsView all reviews →
Airbag control unit Fiat 500 was broken. Hard to believe but they can really repair it! Recommendation!!
Automatically translated · Original: German
From the first phone call, the order processing, to the shipping, everything was done very quickly and professionally. Now I still have to send the repaired unit to the Swedish workshop and then hopefully the Honda can finally pass the HU there again (failed because of the red airbag light). Thanks to Airbag 24 in Berlin 👍👏. Gerd
Automatically translated · Original: German
Fast repair and fast shipping Simply top
Automatically translated · Original: German
Everything works great
Automatically translated · Original: German
Ultra fast delivery, fit really well in the end. There was even a pen and gummy bears included. :D Definitely again, thank you very much!
Automatically translated · Original: German
What is a Mercedes-Benz A-Class V177 Saloon airbag control unit?
In the Mercedes-Benz A-Class V177 Saloon, the airbag control unit is the central unit of the restraint system (SRS). It evaluates the signals from the crash sensors and, in an accident, decides within milliseconds which airbags and seatbelt pretensioners fire. After an accident it stores crash data and locks itself.
Even during normal driving the unit works continuously: it monitors the entire restraint system and indicates faults via the airbag warning light. Without a working control unit, the system cannot react properly in an emergency.
The control unit is fitted in the Mercedes-Benz A-Class V177 Saloon (2018 to 2025). The manufacturer is Bosch. Which version your vehicle has depends on its equipment and year of manufacture.
Airbag24 inspects, repairs and tests your unit. You get your own control unit back, not a different one.
Why is the Mercedes-Benz A-Class V177 Saloon airbag control unit defective?
Usually the first thing you notice is the airbag warning light, which no longer goes out. The most common cause is crash data from an accident, even if no airbag deployed; an ordinary diagnostic tool does not erase it. Other possible causes are aged components, cold solder joints, moisture and corrosion on connectors, and voltage spikes.
What you notice as a driver is usually clear-cut: the warning light in the instrument cluster stays on permanently. If you clear the fault memory, it is full again shortly afterwards. Sometimes the diagnostic tool cannot connect to the control unit at all.
Different causes lie behind these symptoms. Electronic components age over the years, and a cold solder joint can cause contact problems without anything being visible from the outside. Moisture makes connector contacts corrode, so that signals are distorted or missing. Voltage spikes arise, for example, from a weak battery or from jump-starting. At first such faults often occur only intermittently, later they persist.
Common error codes for Mercedes-Benz A-Class V177 Saloon airbag control unit repair
The codes for the Mercedes-Benz A-Class V177 Saloon point to internal unit faults, lost communication, supply voltage that is too low or too high, open circuits in the squib circuits and stored crash data.
The following codes are known:
- B1000 → Airbag control unit fault
- B2500 → Internal control unit fault
- B1561 → Crash data stored in control unit
- U0151 → Communication with airbag control unit lost
- B1315 → Control unit supply voltage too low
- B1318 → Control unit supply voltage too high
- B1420 → Open circuit in driver airbag squib circuit
- B1421 → Open circuit in passenger airbag squib circuit
The codes are read with a diagnostic tool. A code appearing does not in itself prove a fault in the control unit, as connectors, wiring or an airbag module may equally be responsible. Only an inspection brings clarity.
The control unit is connected to the airbag modules and seatbelt pretensioners via the squib circuits. If an open circuit is reported there, the control unit, the wiring or the module may be the cause.
What part numbers are available for the Mercedes-Benz A-Class V177 Saloon airbag control unit repair?
You will find the part number on the label of the control unit; it determines the exact version. Because the numbers within a model series differ by equipment and year of manufacture, it is worth looking at your own unit.
Known part numbers are shown in this list; it is not complete:
- A1779000404
- A1779009515
- A1779000304 (Bosch)
Compare the number on your unit with the list. This only confirms that it is the right unit. Whether it is actually defective is shown only by reading out the fault memory or by our inspection.
The route to repair: first have the fault memory read out. Then disconnect the battery and remove the control unit. After that, create a repair order online and send in the unit. Inspecting, repairing and testing usually take 3–4 working days at Airbag24.
The repaired control unit comes back with all vehicle data and is ready for use as soon as it is refitted — no coding or programming is required.
4.8
Based on 233 reviews
What our customers say
„Works like a charm!“
Leoly3 weeks ago„Airbag control unit Fiat 500 was broken. Hard to believe but they can really repair it! Recommendation!!“
Automatically translated · Original: German
Christian Maegerleinlast week„From the first phone call, the order processing, to the shipping, everything was done very quickly and professionally. Now I still have to send the repaired unit to the Swedish workshop and then hopefully the Honda can f…“
Automatically translated · Original: German
Gerd Goldammerlast week„Fast repair and fast shipping Simply top“
Automatically translated · Original: German
Andreas Foxlast week„Everything works great“
Automatically translated · Original: German
Wolfgang Katenzlast week„Ultra fast delivery, fit really well in the end. There was even a pen and gummy bears included. :D Definitely again, thank you very much!“
Automatically translated · Original: German
Tim Hammer2 weeks ago„I drive a W210 estate. My control unit was broken and because of that I couldn't go to TÜV. I was recommended Airbag24 from a forum. I sent in my control unit. Unfortunately everything was a bit under time pressure and I…“
Automatically translated · Original: German
Franz Dampf2 weeks ago„Motorhome Fiat Ducato. Fault airbag lamp lit permanently, could also not be reset after reading it out. Fault was permanently present. Quick friendly contact with Airbag24, described the fault, known problem was the stat…“
Automatically translated · Original: German
Rene Larisch2 weeks ago„Professionals are at work here, any additional repairs that may arise are carried out without complaint and without discussion...always happy to come back.“
Automatically translated · Original: German
Manfred Gunia3 weeks ago„From the order to the repair everything worked well, airbag control unit installed, the light goes off again as it should, good service, fast repair and return shipping. Thanks 👍👍👍“
Automatically translated · Original: German
Petra3 weeks ago„Got the second airbag control unit from you for another car. Fits, no more error message. Great service Can only recommend. Super fast delivery, and they keep what they promise. A big thank you to this company.“
Automatically translated · Original: German
Mama 43 weeks ago„Super fast service and repair Fast processing“
Automatically translated · Original: German
Dennis Baron4 weeks ago„Works like a charm!“
Leoly3 weeks ago
