status update MY-2015 purchased 3 months ago

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bananapeal

Member
Joined
Jun 3, 2019
Messages
19
model year not "emphatic my"

ok so my parents are using the 2015 MB ED with the range button as a second car in rural area. it is very successful for my dad's commute as he can charge at work for free and skips charging at home. because 3 trips of 30ish miles fit comfortably enough in regular range that he can even skip a charging session! they have rural roads so is easier on gentle driving. very much in love with the silent driving experience.

a week ago it displayed the dreaded "take to shop" warning on dash. he drove it for the week hoping it would disappear. maybe a slight change in noise but can't tell. it is now with the dealer and being operated on for suspected "motor control unit." so not the motor. i did not suspect the power electronics would have issues. eta for parts from germany is unknown. what if they got the diagnostics wrong? our impression is the one electrical tech is just waiting for instructions, what if their back and forth troubleshoot was mistaken? another long wait to repair?

i've read some of the repair threads here and it appears MB will not offer warranty extension if your car is out for months.

loaner is gla250. probably the last thing in their lineup i would've chosen.
 
Oh boy. First thing to do is check your warranty to see if you are just in the 4 year window for parts, including motor. Fingers crossed for your parents.

Here are some random thoughts:

1. MB dealers are supposed to have a trained EV technician but the reality is they have and should take instruction from MBUSA or MBGER as they do not really know what to do. This takes a week or two for proper diagnosis.

2. It could be a software glitch particularly if previous owner did not take into shop for the recall and software updates. I got this message early on but it went away with a software update.

3. Motor control unit is a new one for this forum. You might check the other B250e forum. If they have to replace the part, it might take a while to source the replacement part, several weeks. MB dealer can advise but they don't really know unless they find a part in stock somewhere and can confirm shipment date. Likely will come from Germany. Believe MCU is a MB part, not a Tesla part.

Bummer.
 
banapeal,

What ended up being the issue with your b-class? Did you have to replace the motor?

SA
 
they just got it back today. it appears almost everything that produced torque as its function in one way or another got replaced. they didn't comment on the status of the battery. relevant bits from the report. it is under warranty praise. they should extend the warranty for the month long repair. lol.

Code:
INSPECTED MOTOR - FLUID LEAKING HEAVILY INTERNALLY TO DRIVE UNIT
REMOVED HIGH VOLTAGE CABLES AND BRACKETS.
REMOVED PARK PAWL. DROPPED DRIVE MOTOR AND REPLACED WITH NEW* UNIT.
PERFORMED ALIGNMENT. PERFORMED TEST DRIVE. OK.

Code:
A/C COMPRESSOR MOTOR VERIFIED DEEP HUMMING/DRONING WHEN A/C SWITCHED ON. BEGAN NOISE VIBRATION
HARSHNESS DIAGNOSIS TO DETERMINE SOURCE. FOUND COMPRESSOR HUMMING LOUDLY AT ALL POINTS, REVERBERATING
THROUGH SUCTION AND DISCHARGE LINE.
FOREIGN CONTAMINANT IN COMPRESSOR. INSTALLED NEW*
COMPRESSOR AND REASSEMBLED.

...drove it for a week with service message, didn't notice smell nor motor noise (folks said you'd smell burning coolant). ... how long can we plan this repair to last do you think?

*parts list said reman for both motor and the compressor.
 
bananapeal,

This is good news, only 3 weeks to boot. Could have been longer. Comments:

- Remanufactured parts. So, parts getting harder to find.

- Coolant leak. That is not what you had unless it is connected to ac compressor.

- Remaining warranty. You gotta bring this car in before the warranty runs out for a once over with special attention to the motor, battery and coolant system.

Hope our parents enjoy the ride.
 
it's good they caught it during these last month of warranty. what is concerning is that it isn't clear if the remanufactured units fixed the issue that causes them to leak the fluid after awhile. seems like a degenerative condition of the motor like the milling. or it's just a straight up defect that existed in just a certain production run? are we safe now with the replacement?

FWIW the report i read here about an earlier motor replacement also involved remanufactuered motor and the website for mercedes replacement parts doesn't show a new version just these repaired ones. 3k or so for a motor.
 
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