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I have had the codes read and the it has picked up a error between the front SAM and Master Windscreen motor.
I have checked fuses - 41, 42, and 49 - all appear fine.
Test were run on the stalk switch and passed fine.
Question, are there 2 motors? As fuse diagram states there are x2 wiper fuses. The one mentioned on the error code is 'master', so i assume this will be driver side?
Any other suggestions to fix the issue would be great, thanks.
My car having issue with wipers: both wiper motors are not working immediately when I turn on the car and I have to wait around 4-5 min then it work normaly, there are one error code related to front SAM, wiper fuses and wiper motors but I check on the fromt SAM there are no issues related to fuse, corossion or water damage.
Do you know why wiper motors only run after the car tủn On about 4-5 min?.
Definitely needs diagnosis. The 221 has two independent wiper motors. The slave follows the master under control via a bus signal. You can see this if you switch off the car with wipers on the glass half way. Wait, turn ignition on and one wiper runs to the default position first, then the other.
Wipers stop working if the bonnet closed switch misbehaves, the door switch misbehaves in addition to many other issues. Diagnosis should help even if there were no fault codes.
My car having issue with wipers: both wiper motors are not working immediately when I turn on the car and I have to wait around 4-5 min then it work normaly, there are one error code related to front SAM, wiper fuses and wiper motors but I check on the fromt SAM there are no issues related to fuse, corossion or water damage.
Do you know why wiper motors only run after the car tủn On about 4-5 min?.
Could it be that when temperature drops below freezing the wipers are disabled until windshield bottom edge heating frees the blades from the glass? I don’t know if MB use such a logic but they could. 4-5 minutes could be the set assumed time in the system to melt the snow/ice around bladed?
Of course, if you are in area warmer than freezing then the above does not apply at all.
I have error code 9120 - Fault in communication between N10/1 (front SAM and fuse relay) and M6/6 (Master motor). The weird is everything seem be okay after car turn ON a round 5 min and I can't figures out what is a root cause.
I just realized that wiper motor is not just 12V DC motor, it has electronic control module attached to the motor then therefore failure of master wiper motor could impact to slave motor then therefore mater wiper motor is the first thing I need to inspect and I might swap mater motor with slave wiper motor because they look the same and seem only bracket is different.
I just realized that wiper motor is not just 12V DC motor, it has electronic control module attached to the motor then therefore failure of master wiper motor could impact to slave motor then therefore mater wiper motor is the first thing I need to inspect and I might swap mater motor with slave wiper motor because they look the same and seem only bracket is different.
Part numbers are different. Be careful if you try to swap the master with the slave.
Hi Minh,
Both my wipers quit on me as well. I tool the wiper arms out and am trying to test them with a 12V battery.
But your message mentioned that these motors will not run on a 12V charge because of an attached ECM.
Did you find a way to test the motors?
Hi Minh,
Both my wipers quit on me as well. I tool the wiper arms out and am trying to test them with a 12V battery.
But your message mentioned that these motors will not run on a 12V charge because of an attached ECM.
Did you find a way to test the motors?
Viper motors are controlled via a LIN-bus. The slave motor controlled by the master. Not possible to start the viper motor with a 12 V feed.
I take feom SAM out and inspect for damage but I couldn't figured out any thing wrong with SAM, the SMD capacitors on the SAM also are look good then therefore i did not change capacitor as planned.
I reassembled, clean all fuses contact and bingo SAM and wiper motors working instantly when I switch key to ON.
Update: remove front SAM and clean fuses contact was not help, wiper still intermittent: some time it works instantly when the key is ON, sometimes it work only after 5mins with error code communication issue between front SAM and wiper master motor. I inspect cables between SAM and motor ang they seem be okay.
what part I need to replace? Front SAM or master wiper? Anyway for diagnosis instead part changer?
Earlier inspaction I couldnt find any water damage or corrosion on the fuse pit. Should I remove fuse pit one more time and with sand papaer to clean all of contacts?
Due to earlier when I remove front SAM and fuse for visuall check water damage or any sign of corrosion but I couldn't detect anything but wiper motor working instantly when I re-install but it last for few day only so I believe that culprit of problem is a poor contacts and I decided to remove front SAM for one more time especially when I know that similar issue are resolved by fuse pit replacement.
When I open fuse pit, there are 7 layer of copper cable and plastic separator instead of circuit printed as other model. It make ma a bit nervous when some coper fall out and I afraid that I can't find a correct position for the pieces. Luckily on plastic separator, there are a guide for copper pieces, and it take time to find a correct place but you can't put the copper pieces in wrong position.
I realised that the fuse pit is in good state, however contacts between blades and fues or relays is contact in single point and not durable as other version, and this easily to make a poor connection over the time.
i make a sand paper to clean all fuse and relay contacts and assembly them again and so far so good.
Contact is a point contact so it not durable over a time Coper blade, there are 7 layers like this in fuse pit Many coper blades and they are very easy to fall out if you not extremely care when opening Plastic separator, in this pastic there are some guide to keep blade proper sit in place This is a fuse pit of W211, instead of copper blades with plastic separator, they use printed circuits board, which more easy when disassembly. In addition, contact with fuses or relay is in a row contact, which more durable and stable then pointed contact