Status – BMW
Autonomous Mobility and Safety | Vehicle Dynamics

Notification to Vehicle Manufacturers & Logistics
› Potentially suspect Parts sent to Customers
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BMW Spartanburg was notified on February 3rd 2020

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Total qty. 18,406 suspect

Spartanburg Part N° 5A0B13901; -18,942qty shipped (536 parts returned, 3,843 parts more targeted for return)

Ford Chicago and Louisville were notified on February 4th 2020

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Chicago Part N° L1MC-2D335-CB -18,635qty shipped, Chicago trading; 550qty shipped

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Louisville Part N° LX6C-2D335-KA -13,455qty shipped

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Hermosillo Part N° LX6C-2D335-KA -53qty shipped (53 parts are targeted for return)

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Cuautitlan Part N° LJ9C-2D335-AB -121qty shipped (121 parts are targeted for return)

Confidential

Total qty. 32,814 suspect

9 March 2020
VED Quality, © Continental AG

2

Defect Description
armature inside
hydraulic valve
hydraulic valve armature

concerned hydraulic valve at max.
three positions inside hydraulic valve
block
pressure feed
valve

OK Part

Electronic Brake
System MK C1

simulator
valve

NOK Part

Confidential

9 March 2020
VED Quality, © Continental AG

3

Root Cause at Valve Assembly Continental Plant Morganton

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Due to crash at the armature assembly station the assembly axis became misaligned

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Machine stopped and Technician adjusted the alignment w/o recognizing a permanent deformation – after adjustment line was re-started

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Due to the self centering capability of the assembly head, the machine started to create sporicidal failures – with detection of cracked plunger
inside a customer return part, assembly line was stopped at 6th of February

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Clean date of further completed MK C1 units deliveries with containment valves from sister plant Mechelen in Belgium – 7th of February

Confidential

9 March 2020
VED Quality, © Continental AG

4

Defect Occurrence Probability
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8 x 0-mileage Complaints from Customer
› 6 x from BMW
› 2 x from Ford
› Defect at simulator valve
– Customer Complaint = “hard brake pedal”
– Customer Complaint = “pressure feed valve unwanted open” – DTC0x4808D1, Red & Yellow
› Defect at pressure feed valve
warning light ON

› Suspected time frame from 7th to 30th of January 2020 based on production dates of valves investigated and found with cracked
plunger

› Tear down and analysis of valves from suspect time frame (Morganton stock)
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6 out of 315 plungers found cracked

= 1,93% NOK

(with 90% confidence level NOK rate is within 0,83%-3,72%)

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Depending on MK-C1 variant, either 2 or 3 valves are used inside 1 hydraulic valve block

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HECU variant with 3 valves, expected NOK rate

= 2,47 to 10,8%

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HECU variant with 2 valves, expected NOK rate

= 1,65 to 7,30%

Confidential

9 March 2020
VED Quality, © Continental AG

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Defect Severity
› Simulator Valve Failure
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Pressure build up OK - >6.43m/s² @500N confirmed
Hard pedal possible (down to 4mm rod travel  approx. 16mm pedal travel)
Sporadically behavior based on plunger tip position
Controllable for the driver (noticeable changed pedal feel), no vehicle instability, no yawing
Control functions remain active (ABS / AYC) and ensure vehicle stability
Regulatory Affairs Frankfurt: No violation of ECE13h nor FMVSS norms

› Pressure Feed Valve Failure
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Pressure build up OK but - sporadically delayed pressure decrease in one circuit after releasing the brake pedal

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Approx. 30bar delta pressure for 200ms (reduced volume flow through Pressure Feed Valve)
Max. 80bar pressure remaining for 0.8…1.0s inside one circuit

Controllable for the driver, no vehicle instability, no yawing
Control functions remain active (ABS / AYC) and ensure vehicle stability
Regulatory Affairs Frankfurt: No violation of ECE13h nor FMVSS norms

Confidential

9 March 2020
VED Quality, © Continental AG

6

Thank you
for your attention!

Confidential

9 March 2020
VED Quality, © Continental AG

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