Mercedes B250e
Electric motor repair
The economical alternative to the overpriced replacement motor. We repair your Tesla-based Mercedes drive with certified precision.
Why the Mercedes replacement motor
is not a solution
Mercedes Austausch
Often an economic total loss, since the motor value exceeds the residual value of the vehicle.
- close Starre Ersatzteilpolitik
- close No individual replacement of bearings
ESDI repair
Precise repair of defective components instead of a blanket replacement of the entire unit.
- check Repair of the Tesla LDU core
- check Hochwertige Keramiklager
Gebrauchtmotor
High risk. The known weak points (coolant seals) are often already present.
- warning Ungewisse Laufleistung
- warning Keine Langzeit-Garantie
"At a current market value of around €12,000 – 15,000 for a Mercedes B-Class Electric Drive, a Mercedes quote of over €18,000 for a new motor is effectively the end of the vehicle. We preserve the value of your Mercedes."
Why is there a Tesla motor in your Mercedes B-Class?
During the years of the cooperation, Tesla supplied the complete drive unit and the battery pack for the B-Class Electric Drive. Technically, the Mercedes motor is a modified Tesla "Large Drive Unit" (LDU), as also used in the Model S and Model X.
That means for you: we use our in-depth Tesla know-how to offer Mercedes customers the same high-quality repair methods that we have been perfecting for Tesla vehicles for years.
End of the cooperation in 2014
Since the end of the collaboration, Mercedes has greatly cut back support for this specific Tesla technology, which explains the extreme prices for complete replacement units.
Symptome an Ihrem Mercedes B250e
Grinding noises
A distinct humming or grinding from the rear area that increases with speed. Often a bearing failure.
Plötzlicher Leistungsverlust
The vehicle goes into turtle mode while driving or shuts down completely.
Fehlercode U05959A
Typical error message in the diagnostic system, pointing to a communication fault in the drive unit.
Coolant in the motor
The "Mill-Seal" problem: defective shaft seals let coolant enter the windings.
Vibrations when accelerating
Imbalance or mechanical play within the Tesla LDU unit of the Mercedes.
Moisture at the flap
Inspection note: visible residue on the inspection flap of the drive unit indicates internal leakage.
Frequently asked questions about the B250e motor
Is the Mercedes B250e motor really from Tesla? expand_more
Why is the repair so much cheaper than the replacement? expand_more
How long does the repair take? expand_more
Unser Reparaturprozess
How we repair your Mercedes B250e electric motor
The Mercedes B250e (W242) and the Mercedes B-Class Electric Drive use an electric motor developed by Tesla — the so-called Small Drive Unit. This drive unit is based on the same technology as the Tesla Model S Large Drive Unit and shares many mechanical components. This is exactly why ESDI, as a Tesla motor specialist, is the ideal partner for your Mercedes B250e electric motor repair.
The most common defects on the Mercedes B250e motor are bearing damage (grinding noises while driving), coolant ingress from defective seals, power loss from worn windings and the dreaded error code U05959A. At Mercedes a replacement motor often costs over €8,000 — an economic total loss for a vehicle with a residual value of €10,000-€15,000.
At ESDI we specifically repair the defective components: ball bearings, oil seals, shaft seals and — if necessary — the rotor. Our HV-certified technicians work with Tesla drives every day and know every weak point. The repair usually takes 5-10 working days, and you receive a binding fixed-price quote in advance.
Mercedes B250e repair: location and process
Our technology centre is located in Herford (East Westphalia-Lippe), reachable at 05221 771950. You can bring your vehicle yourself or send in the removed motor. We also offer support with logistics and work with partner workshops throughout Germany that handle removal and installation.
For your Mercedes B250e electric motor repair we first need a diagnosis. Contact us via the form on this page or by phone — we will prepare a non-binding quote for you within 24 hours.
This is what a total loss from dry running looks like
The following images come from a recent overhaul of a Mercedes B250e drive unit in our workshop. The motor was operated over a longer period without sufficient lubrication and under high load — with devastating consequences.
Kugellager zerstört
Bearing cage disintegrated, massive discolouration from overheating. The metal abrasion has spread throughout the entire housing.
Metal sludge instead of gear oil
Instead of gear oil, we found a viscous black paste with visible metal shavings — the oil was completely degraded.
Schrägverzahnung komplett zerstört
Due to dry running and extreme overheating, the gears of the reduction stage are irreparably damaged.
Kunststoffteile geschmolzen
The temperatures in the gearbox were so extreme that plastic components melted — a sign of dry running at full load.
Ölablassstopfen voller Abrieb
At the drain plug, instead of oil only viscous paste with metal particles — lubrication had not been present for some time.
Sensor komplett verkrustet
The position sensor is completely coated with burnt oil and metal abrasion — no longer functional.
The 4 phases of a bearing failure — and when you should act
A bearing failure on the Mercedes B250e does not happen overnight. The motor gives clear warning signals — the earlier you react, the cheaper and simpler the repair.
Quiet humming or droning
Beginning bearing wear first manifests itself as a slightly changed running noise — an additional humming or droning that was not there before.
Repair: pure bearing replacement — low effort, low cost.
Mahlende Geräusche & Vibrationen
The bearing wears further, the noises become considerably louder and noticeable vibrations occur. Metal abrasion begins to contaminate the gear oil.
Repair: bearing replacement + oil change + thorough cleaning.
Leistungsverlust & Fehlermeldungen
The vehicle shows error messages or goes into limp-home mode. The contaminated oil acts like an abrasive on all moving parts in the gearbox.
Repair: possibly still feasible, but scope and costs rise considerably.
Trockenlauf & Überhitzung
Bearing completely destroyed, no functional oil left, gears irreparably damaged by overheating, plastic parts melted. The motor can no longer be repaired.
Solution: only a replacement motor possible now — highest cost.
Unser Rat: Lieber einmal zu früh als einmal zu spät
Do you hear unusual noises, feel vibrations or see an error message? Do not wait. Call us at 05221 771950 — an initial assessment is free with us. The earlier we see the damage, the more we can do for you and your vehicle.
Professional overhaul — step by step
Every drive unit is completely disassembled, assessed and properly repaired at our facility. Here you can see how we work.
Drive unit on our workbench — ready for complete disassembly and diagnosis.
Opened gearbox — differential gear, reduction stage and bearings are assessed individually.
Housing with bearing seats — this is where the new ball bearings are inserted.
Tesla part number 1004706-02-M — the drive unit in the Mercedes B250e is a Tesla unit.
Save your Mercedes from total loss.
Send us your vehicle data or call us directly. Our experts analyse your fault pattern without obligation.
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