Bosch 0445 e A-number Mercedes: cross-reference iniettori

A Bosch 0445… number and a Mercedes A-number printed on the same injector refer to the same physical part from two catalogues. Bosch labels it by its own 10-digit part number; Mercedes labels the identical injector with an A-number for its service system. Match either number to your car and you have confirmed fitment.

This two-number system trips up a lot of buyers, so here is exactly how it works — and how to read both numbers off the injector in your hand.

How does the Bosch 0445 numbering work?

Bosch common-rail diesel injectors share a 10-digit part number that begins with 0445. The digits that follow identify the injector family and the specific application:

• 0445 11x… — a common-rail injector family used across many modern diesels. The full 10 digits (for example 0445118034) pin it to one exact specification: nozzle, body, and calibration.
• The number does not change with the car brand. The same 0445… injector can appear on vehicles from several manufacturers if they share the injector design.

The key point: only the complete 10-digit Bosch number confirms the part. A partial match ("it's a 0445 11-something") is not enough — the last digits define the exact injector.

How do Mercedes A-numbers map to Bosch numbers?

Mercedes doesn't order parts by Bosch numbers in its workshop system — it uses its own A-number (an 'A' followed by ten digits, e.g. A6540700300). Each A-number corresponds to one Bosch part number. So for any OM654 injector there are two labels for one component:

• The Mercedes A-number — what a Mercedes dealer or EPC catalogue lists.
• The Bosch 0445… number — what Bosch and most aftermarket suppliers list.

Because the mapping is one-to-one, confirming either number against your vehicle confirms the part. You do not need both — but seeing both is the strongest proof you're buying the right injector.

Where are the numbers on the injector body?

Both numbers are laser-etched or printed directly on the injector, usually on the metal body below the electrical connector. On a Bosch unit you'll typically find:

• The 0445… number (Bosch part number), sometimes with a smaller batch/serial line beneath it.
• The Mercedes A-number, etched separately.
• A short calibration / IMA code (letters and digits) used when coding the injector to the ECU.

Wipe the body clean and photograph it in good light — the etching is fine and easy to misread. If a seller can't show you a clear photo of these numbers, treat that as a warning sign. Every listing in our fuel-system category shows the OEM number, cross-references and real condition photos for exactly this reason.

The three OM654 injector pairs in our catalogue

For the Mercedes OM654 2.0d, here are the exact number pairs and the models they fit:

| Mercedes A-number | Bosch number | Fits | |---|---|---| | A6540700300 | 0445118034 | C220d (W205), E220d (W213), GLC220d (X253), Sprinter | | A6540730087 | 0445118009 | OM654: W205, W213, GLC, GLE (piezo) | | A6540700187 | 0445117048 | OM654: C220d, E220d, GLC |

Click through for full fitment and photos: A6540700300 / 0445118034, A6540730087 / 0445118009 piezo, and A6540700187 / 0445117048.

Why does matching either number confirm fitment?

Because the A-number and the Bosch number describe the same specification, a match on one guarantees the nozzle geometry, flow rating and connector are correct for your engine. What a number match does not do is handle calibration — every used injector still has to be coded to your ECU. If you're unsure whether that applies to you, read our injector coding (IMA) guide. And before ordering, check the symptoms actually point to the injector using our OM654 injector failure guide.

FAQ

Is the Bosch number or the Mercedes number more reliable for ordering?

Either is reliable on its own, because they map one-to-one. Ordering with both numbers to hand simply removes any doubt and makes cross-checking a listing faster.

My injector shows a 0445 number but a different A-number than the seller lists — is it wrong?

Possibly, or the seller may be listing a supersession. Match the Bosch 10-digit number to your application and ask the seller to confirm the mapping. Don't buy on a partial number.

Do aftermarket injectors use the same 0445 numbers?

Genuine Bosch units carry the true 0445 number. Be cautious with unbranded parts claiming a Bosch number without the Bosch etching — inspect the body markings and buy from sellers who show them.