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5 Posts
Discussion Starter · #1 ·

I have an A180d with the premium plus pack. I do not have traffic sign recognition.

Whilst driving on a stretch of road with some roadworks where a temporary speed restriction was in force at 30mph (road is usually 40mph) i noticed my car read the 30mph temporary sign and briefly the speed limit warning on my drivers lcd changed from 40mph to 30mph before quickly changing back.

I can only assume the forward facing camera picked up the sign as the roadworks were only there for a day so I do not believe gps / sat nav would have played a part.

I also get semi regular messages when driving in fog or spray etc that ‘traffic sign recognition not available’.

Given I don’t have traffic sign recognising specced on my vehicle though, how can this be?

Is it literally just a case that the car is good to go with this or other additional features but there is a box unticked in the software to say I haven’t paid for it?

If so, is there a way to activate any of these features?

Super Moderator
4,002 Posts
Which month and year was your car built, and do you have Advanced (AR) Nav?

AMG Line Premium Plus cars built from July2020 for example, have TSA Traffic Sign Assist included.

It sounds like you might be referring to the simpler variant, SLA Speed Limit Assist installed in your car.

There are retrofit upgrades available by 3rd parties to upgrade SLA to TSA for other M-B models, but not yet for the W177.

5 Posts
Discussion Starter · #3 ·
It’s a 2019 registered in Julydon’t have advance nav. I have nothing beyond what the premium plus pack comes with as standard.

is there a way to tell when it was manufactured?

Apologies if this is an obvious answer!

Super Moderator
4,002 Posts
Sounds like SLA Speed Limit Assist, have a search of this forum, there are many threads and posts about SLA and its features and shortcomings.

5 Posts
Discussion Starter · #5 ·
Thanks for your reply.

I did consider this.

It isn’t an option specced on my car and I don’t have this option in my assistance menu within the cars settings!

I’m confused!

Super Moderator
4,002 Posts
SLA would have been standard (possibly depending on production date), and not an option.

Even the SE would have been fitted with SLA and Lane Keeping Assist as standard, for example.


5 Posts
Discussion Starter · #9 ·

that’s a lot of info!


ModelA 180 d
ColourPolar white - standard finish (149)
Production Date2019-06-20
Order Nr.09536XXXXX
Production Nr.69XXXXX
149Polar White - Standard Finish
05BOperator's Manual + Service Booklet-English
149UPolar White - Standard Finish
15UPre-Installation For MB-Link Smartphone Integration
20UKeyless Rental
213Speed-Sensitive Power Steering/Vario Steering
218Rear View Camera
235Active Parking Assist
241Left Electric Adjustable Driver's Seat With Memory
243Active Lane Keeping Assist (Camera)
249Automatic Dimming Inside Rearview Mirror And Outside Mirrors
255BMB-Mobilo With DSB And GGD
258Collision Warning System With Active Brake Application FCW-Stop
270Aerial For GPS
275Memory Package (Driver's Seat, Steering Column And Mirror)
286Luggage Nets On Left And Right Driver Seat Backrests
287Through-Loading Feature
2U1Radiator Shutter
2U8Alternative Refrigerant
310Double Cup Holder
335BLanguage Of Instrument Cluster/HU - English
345Rain Sensor
351ECall Emergency Call System
355Preinstallation For Retrofitting Navigation System
362HERMES Communications Module LTE
365Hard Drive Navigation
367Live Traffic Capability
3U6HU Country Set For ECE/RoW
400Folding Armrest In Rear
413Panoramic Sliding Sunroof/Glass Roof
428Steering Wheel Gearshift Buttons/Steering Wheel Gearshift Paddles - Painted
4297-Speed Automatic Dual-Clutch Transmission
440Cruise Control
45810.25" Instrument Cluster Display
474Diesel Particulate Filter
475Tire Pressure Monitor (TPM)
500Electrically Folding Exterior Mirrors
502Free Map Data Updates For 3 Years
504Speed Sign Recognition
51BRating, Country Group EURO-NCAP
51UHeadliner, Black Fabric
537DAB Digital Radio Standard (Digital Audio Broadcast)
537LGreat Britain And Northern Ireland
543Sun Visor With Additional Function
548MBUX Multimedia System
551Standard Anti-Theft Alarm System (ATA)
581Automatic Air Conditioning
5U3Radiator Grille With Adaptive Closing Function
641Dynamic LED Headlamps, Left-Hand Traffic
666Prod. Prot. F. Freight Pkging W/O Tie-Down Hooks
677AVANTGARDE/Standard Suspension
6P5Sales Control Code For Code 475 Request
72RLight-Alloy Wheel 10-Spoke Design 17" All-Round
73BRoller Blind Compartment Closed
79BPre-Installation For DAB Digital Radio Standard
7U2Seat Model Variant 2
800YoM 19/1
853Advanced Sound System
859Central Display Mid (9-Inch To 11.5-Inch)
873Left And Right Driver's Seat Heating
877Ambient Lighting
882Sensor System And Siren For Anti-Theft Alarm System
885Enhanced Anti-Theft Protection
889Keyless Go
8U6Assistance System Steering Wheel Control Changeover
8U8I-Size Marking (ISOFIX Successor)
927Exhaust Treatment, Euro 6 Technology
968COC Document For Euro6 Tech. Without Reg. Cert. Part 2
989Identification Label Under Windshield
98BUpper Radiator Shutters
998Steuercode Umstellung WLTP Mit RDE
B09Refrigerant Compressor With Magnetic Clutch
B18Spectacles Compartment
B59Drive Program Selection Switch (AGILITY SELECT)
D53No Code Designations Currently Available
D5BNo Code Designations Currently Available
F177Model Series 177
GAAutomatic Transmission
GB3NNo Code Designations Currently Available
H55Trim Elements - Plastic IMD Carbon Fiber Look (2B48)
HARear Axle
K13Control Code For Service Interval 25000 Km
L3ESport Steering Wheel - Smooth Split Leather
M15Displacement 1.5 Liter
M608Inline 4-Cylinder Diesel Engine OM608
O15No Code Designations Currently Available
P44Parking Package
P54Anti-Theft Protection Package With Preinstallation For Collision Detection
P59Urban/Progressive Package
PACValue Package
PYAControl Code For Sales
PYFControl Code For Sales
PYOControl Code For Sales
PZFControl Code For Sales
PZXControl Code For Sales
RNo Code Designations Currently Available
R01Summer Tyres
U01Rear Belt Status Indicator
U10Front Passenger Seat With Weight Sensor
U12Velour Floor Mats
U22Lumbar Support Adjustment
U25Illuminated Door Sill
U54Compound-Link Axle
U59Seat Comfort Package
U60Pedestrian Protection - Active Hood
U62Light And Sight Package
U79BLUETEC (SCR) Diesel Exhaust Treatment, Generation 3
V50Speed/Load Index 91W
VLLeft Front Axle Half
VRRight Front Axle Half

1,129 Posts
In my view SLA is a very badly implemented feature that cannot be relied on to give the correct speed icon.

SLA is there on all A Class models to satisfy NCAP testing but my guess is that MB developed TSA, which works very well & integrates camera sign recognition with Satnav data, then disabled the Satnav part expecting it to work but in reality some of the time it does not.

As for the error message you get in rain & fog, this is because the camera cannot see anything and it's just letting you know.
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