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Lou P. master tech
Lou P. master tech, Mercedes Technician
Category: Mercedes
Satisfied Customers: 3724
Experience:  15 years master certified 100% fix rate and have access to factory radio codes, wiring, and instructions.
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I must explain This first: car is w221 s-class without

Customer Question

Hello, i must explain This first : car is w221 s-class without xenon , halogen h7 dipped beam
Halogen h9 High beam
And h11 is Fog - car is s320 cdi 2008 pre facelift.
2 months Ago i installed led Bulbs in license and parking lights, next Day i Got airbag malfunction, some Days after i Got srs light.. Took car to 3 diffrent mechanics and Star Said problem is y51 solenoid valve front left air shock and srs is coallison sensor front left.
Some weeks after, when i decided to buy new shock - The led Bulbs Started to flicker so i changed back to normal w5w 12v 5w Bulbs and all errors dissapeard The next Day!! Even tho Star Said something is wrong with The specific places and mechanic Said to replace Them, it turned out to be The led Bulbs causing errors!!!
So i Removed Them, and only drove with hid kit h7 for dipped beam..
So for a Month all was good until i stumbled upon a box of Bulbs online, they were all halogen Bulbs , but xenon look halogen Bulbs! You know , The blue glass halogen Bulbs, i ordered The box that contained h7, h9, h11 and w5w, all i needed to upgrade my dipped beam, High beam, Fog beam and side lights into pure White without using led Bulbs!
So i installed The h7 dipped beam (because my hid kit one Bulb Went bad, so was wiring for replacement)
Also installed h11 Fog and side lights.
They Worked fine and were Nice White Color, when my new hid bulb arrived, and i tryed to Remove The h7 dipped beam
Bulb, it was stück! I had to pull hard, and hell it had Melted The socket and some wire harness too! The other side loooked fine and Came out no problems, installed hid so i thought it was fine.. Some days after i Got airmatic light again! Followed by a srs light that Came on and OFF..
I decided to Remove The Fog bulb, The connector Went out easly but The bulb was so stück i had to pull with a tool and hell ! It had Melted The Fog housing!!!! I put On original Bulbs again and errors still there, so i decided to install a more expensive canbus error free Mercedes hid kit... Errors still there.... I decided to change The Melted h7 connector On The side that was visibly Melted, error still there + now srs is CONSTANT!
Please help...
Submitted: 1 year ago.
Category: Mercedes
Expert:  Lou P. master tech replied 1 year ago.

Hello. Sounds like you are having quite the experience with bulbs. So I can tell you that there is no correlation between the light systems and the airbag or suspension systems. They do work WITH one another BUT they will not cause random fault codes. So what exactly are the fault code numbers and the fault code descriptions. ?

Customer: replied 1 year ago.
Hey
Fault codes Are y51 for airmatic, solenoid valve and code for srs i forgot but its coallison sensor.When i had led Bulbs in car first i Got The errors when i Removed Bulbs they dissappered, it was canbus related errors! The car is sensitive
Im
Certain there is nothing wrong with The suspension or srs , first time they dissappeared they were gone and suspension was working perfectly ! Also Star Said that there Are no codes anymore.
But when i installed The halogen xenon Bulbs and Removed Them to see The damage On my h7 connector , the same problems started ( Well after 1 Month from The old problems dissapeard) same errors..
I have just changed The Melted connector at a auto electrican and now srs is On constantly, should i change other headlights h7 connector too? And perhaps ADD Load resistors On The Fog lights? To imitate The computer to belive that The normal standard Bulbs Are definatley back in?
Customer: replied 1 year ago.
AS soon AS i Removed The halogen xenon look Bulbs that Melted my h7 connector and Fog assembly a little, errors started..
I am suspecting bad connections / canbus errors computer warnings.. Im so certain that neither OFF The airmatic og srs is faulty since both errors Came when i used cheap led Bulbs and both dissappered when i Removed cheap led Bulbs.
Expert:  Lou P. master tech replied 1 year ago.

well like i said, i understand why you think the bulbs are related, BUT a can bus fault will not give you SPECIFIC faults like the Y51, it will give you CAN DATA BUS faults for control modules, does this make sense? a faulty bulb or different bulb will only affect the bulb circuit.

Customer: replied 1 year ago.
how Can it be then that when i Removed led Bulbs , all errors dissappered back then for a Whole Month?
Expert:  Lou P. master tech replied 1 year ago.

the y51 valve block is wired directly into the air suspension control module then over can data bis the module is connected to the other modules on the chassis can. so , in short, if the bulbs were a issue you would have hundreds of fault codes, not 2 fault codes. does this make sense?

Customer: replied 1 year ago.
I did also Get parking sensors stopping working for Like 10 seconds, electrical seat fault (no description in Star but seats working fine)
Expert:  Lou P. master tech replied 1 year ago.

ok lets stick with one issue at a time . so we can stay on the same page.

Customer: replied 1 year ago.
Yep but bro your denying my claim
That led Bulbs in license plate and side lights causes following noticeable errors - airmatic failure, srs light, and parking sensors sometimes turning off.
Once theese Bulbs were out, all was solved, up until The fool i am i installed halogen xenon look Bulbs without researching The Risks. When theese Bulbs were Removed, errors returnerd.
Customer: replied 1 year ago.
AS explained, The h7 connector was damaged so i changed it yesterday, when i Came home - instead OFF getting srs light sometimes now it is constantly On.
Expert:  Lou P. master tech replied 1 year ago.

sir, i am 15years mercedes technician, one of the best, ***** ***** trying to help you, you are here because you need help correct? i am not calling you a liar, or anything like that, i understand you believe what you believe, BUT i can prove to you otherwise if you are willing to work with me.

Customer: replied 1 year ago.
My English grammar or vocabulary is NOT The Best, im
NOT trying to Call you Liar hehe, or anything bad.
I just need need to know How Come led Bulbs could Cause theese errors, and fix Them once they were Removed :)
Expert:  Lou P. master tech replied 1 year ago.

they cannot.

Customer: replied 1 year ago.
yeah The mechanic Said The same.
But apparently they did Cause The issues , since The issues dissappered magically The second they were Removed
Customer: replied 1 year ago.
A guy ive heard OFF spent almost 7.000 US dollars fixing his VW for months at The dealer, they could NOT fix it, problem turned out to be led bulb causing issues
Expert:  Lou P. master tech replied 1 year ago.

ok, if you cannot believe this then i will have to leave you as you will not allow me to help properly.

Customer: replied 1 year ago.
Sorry then ok please try to help me
Expert:  Lou P. master tech replied 1 year ago.

and if you believe the bulbs are the issue, why do you still want to install new bulbs?

Customer: replied 1 year ago.
I Want to installed Load resistors in my canbus hid kit in dipped beam for increased resistance and Load resistors + error free h11 led Bulbs in Fog light to create a stronger illusion of The original Bulbs
Expert:  Lou P. master tech replied 1 year ago.

cars are difficult to say why something took 1 month to show failure again, let me ask you did you wire in the bulbs with wiring from the car? or simply plug it into the origional headlamp connectors?

Expert:  Lou P. master tech replied 1 year ago.

you did not splice into any wires did you?

Customer: replied 1 year ago.
first time months Ago , i used led Bulbs directly in The original connectors for license plate and for side lights.
Second time, The xenon look halogen Bulbs were also directly fitted into The connectors.
The xenon canbus hid kit for dipped h7 beam was also directly fitted in, plug and play.The new connector The mechanic put On for me yesterday , was The h7 connector for w210 (only part at dealer) , it had 1 Brown wire and 1 Yellow wire.
The mechanic cut OFF old connector, spliced The 2 original Brown wires together with The 1 Brown wire from
The new connector. Lights Are working but srs is now On 24/7 unlike before when it was On for 2 seconds then OFF for days
Customer: replied 1 year ago.
If The halogen look xenon Bulbs could damage The socket for h7 , and MELT The Fog housing.
Theese Are visible damages.
Could it NOT have short circuted or anything Else thats NOT visible?
Expert:  Lou P. master tech replied 1 year ago.

if it short circuited inside the headlamp it would only affect other lamp issues inside the housing, most times the aftermarket bulbs do not fit tight into the oem connectors so they create heat from looseness and that causes them to melt.

Customer: replied 1 year ago.
you Are certain that Changing The second h7 connector and also buying Load resistors Will NOT help?
Expert:  Lou P. master tech replied 1 year ago.

here is the y51 its the left front shock. so i can assure you the bulbs will have nothing to do with a shock.

Expert:  Lou P. master tech replied 1 year ago.

the only time you need the load resistors is when you install a bulb and the dash still says bulb defective since it does not recognize the bulb.

Customer: replied 1 year ago.
Is The y51 component Electric?
Expert:  Lou P. master tech replied 1 year ago.

yes., but the y51 also has 2 sub components a Y51y1 and Y51y2 and are all a common symptom of a failed shock. or bad wiring at the axle.

Customer: replied 1 year ago.
It also Said y51y1 Star . Right
Customer: replied 1 year ago.
Can you explain to me what Will happen if there is loose connections somewehere / or if cheap led Bulbs Are installed?
Expert:  Lou P. master tech replied 1 year ago.

if there is a loose connection, a melted connector will be the result., also if cheap led bulbs are installed a message on the dash will come on saying "bulb defective"

Customer: replied 1 year ago.
Can you confirm that The canbus system / car computer is diffrent from car to car , model to model and Can be more sensitive than other cars from same
Make model and year?When The srs light comes On, The problem
Must be fixed and then The light On dash Will only be turned OFF using a special tool or Star Right?
Expert:  Lou P. master tech replied 1 year ago.

ok the can data bus is not a control module, its a communication system. its the same as this,

you are a teacher and there are 10 students using computers in your classroom. the teacher is the gateway and when a student types a message it first goes to the wires that are connecting all the computers together and the message goes out to all the computers , and if the message is specific to the teacher than all the other students ignore the message and the teacher receives the message. so the can data bus is the same, its basically 2 wires that all the modules in the car communicate on

Expert:  Lou P. master tech replied 1 year ago.

no cars are more sensitive

Expert:  Lou P. master tech replied 1 year ago.

and the light can only be turned off with a scanner like the star, that can read the modules.

Expert:  Lou P. master tech replied 1 year ago.

so in short, your lights are not the issue, you have other faults., they are 100% separate now if you get me the codes i can help diagnose the issues. hope this clears it up for you . Please take a second and click the box and rate my service GOOD OR EXCELLENT SERVICE if you feel I have been helpful and please request me in the future. If you feel I have not been helpful please DO NOT RATE BAD OR POOR AND WASTE YOUR MONEY , I will opt out to see if another expert can provide more or better assistance so you're not wasting your money!!. Thanks for choosing just answer. Lou. also , if you feel i deserve one , BONUSES are GREATLY APPRECIATED !

Customer: replied 1 year ago.
Ahaaaa... So all electrical components in The car Are communicating through The canbus.. ?
Expert:  Lou P. master tech replied 1 year ago.

YES!!!!!!!!!!!

Expert:  Lou P. master tech replied 1 year ago.

:)

Expert:  Lou P. master tech replied 1 year ago.

now can bus led bulbs are a little exaggerated, the bulbs are not on the can bus.,

Expert:  Lou P. master tech replied 1 year ago.

what happens is the wires come from the front sam control module, the module looks for the proper resistance in the circuit, if it does not see the proper resistance then it shuts the circuit off. so thats why you have to add load resistors.

Expert:  Lou P. master tech replied 1 year ago.

make sense?

Customer: replied 1 year ago.
Well Then Why is it impossible that if a faulty bad led bulb / bad connection is present, The canbus gets wrong message and Therefor is making all sorts of errors? Ive heard from more people that the wrong bulb Can ruin a entire car, i expierienced it myself sir.. How Will you explain The errors dissappered when i Removed The bad led Bulbs back then? srs was On for weeks... Turned OFF Right away, so Did airmatic next Day.. srs turned OFF without a Star diagnoser or tool! :oo
Expert:  Lou P. master tech replied 1 year ago.

srs fault codes will remain in the car until the fault goes away, now if the fault stays away after the key is cycled 50 times, the light will go off on its own.

Customer: replied 1 year ago.
Key was not cycled 50 times bro The fault just dissappered when The guy put in The normal Bulbs back and i had to turn On car to see if they were working , i turned On car and Bam
Fault dissappered? Actually... The key was turned one time, then he changed Bulbs and i noticed error was gone.
You know Why?
Customer: replied 1 year ago.
Why did The airmatic fault dissappered The Day after i changed to original Bulbs?
Expert:  Lou P. master tech replied 1 year ago.

ok, at this point i see we will never agree. i will opt out . i hope you get this figure out and i wish you all the best. im sorry i wasted your time. i would appreciate you not rating negative if you disagree another expert may be along to help. Lou

Customer: replied 1 year ago.
Wait
Expert:  Lou P. master tech replied 1 year ago.

wait?

Customer: replied 1 year ago.
My car has h7 dipped beam, The connector has 2 Brown wires and 1 Yellow, i bought The w210 h7 rep kit containing new connector, This had only 1 Brown wire and 1 Yellow, The auto electrican cut out The original socket and spliced The 2 Brown wires together and then spliced to The new connectors one Brown wire.. Is This ok?Srs light before was On for 2-3 seconds , then Went OFF, could happen once Every 2-3 days, just turn On for 2-3 second then OFF again.Now after he changed socket its On constantly.Also Can you explain Why my h7 connector has 3 wires? 2 Brown and 1 Yellow
Customer: replied 1 year ago.
Why Do you just Quit? Bro im tælling you... Srs light Went OFF and airmatic malfunction dissappeared.. Then car drove perfect! All This after removing The led Bulbs..
Dont you belive This?
Expert:  Lou P. master tech replied 1 year ago.

im sorry, i dont think i can provide any assistance to help with what you seem to say is happening, since there is no direct link between the bulbs and the srs or suspension system.

Customer: replied 1 year ago.
Ok?? I have NOT Been helped im afraid.. How Can i Get a refund , or chat with another expert?
Expert:  Lou P. master tech replied 1 year ago.

when i opt out the other experts will see the post and hopefully one pics up. as for the refund if you wish all you have to do is follow the customer service links on your end. there is a option to self process. take care. i wish you the best., lou

Customer: replied 1 year ago.
You keep denying what has happended to me.. I have requested refund, is there anything Else i must Do? Can another expert give an second opinion?
Customer: replied 1 year ago.
H7 connectors Are usually 2 wires, The rep kit from dealer also 2 wiresAlso Can you explain Why my h7 connector has 3 wires? 2 Brown and 1 Yellow
Expert:  Lou P. master tech replied 1 year ago.

they sold you the wrong connector, the two wires are ground that is shared between the headlight and the turn signal on a older model, u only have to use one of the wires.

Customer: replied 1 year ago.
You misunderstood Lou, my original connector had 3 wires, 2 Ground and one Yellow wire, new connector from
Dealer has 1 Ground and 1 Yellow, The auto electrican spliced The 2 original wires from headlight to The new connectors Brown wire .. Is This allright?Any Why did my headlight even have 2 Ground and 1 Yellow wire?
Also all is working fine now, just that srs is now On all The time unlike before when it was for 2 seconds Every couple a days
Expert:  Lou P. master tech replied 1 year ago.

Sorry I did misunderstand. My apologies. I just had a similar issue with a headlight connector.

Customer: replied 1 year ago.
Thats ok, do you know The answer to my question ?
Expert:  Lou P. master tech replied 1 year ago.

No I do not. I apologize.

Customer: replied 1 year ago.
You dont know Why my h7 connector has 2 Ground wires and 1 Yellow? Lou?
Customer: replied 1 year ago.
Lou?
Customer: replied 1 year ago.
W220 h7 headlight has same wiring harness AS w221 pre facelift with h7 headlight, agree?
Expert:  Lou P. master tech replied 1 year ago.

Hey man , hope your weekend is good so far. Let me get back with you tonight. I have family functions today :). I will try again to assist. BUT if you are going to ask for a refund in the end no matter what I need to know as I will not be paid until you accept my answer positively , but if you rate me and yen ask for a refund it gets taken away. So if I am going to help I need assurance that this will end positively for both of us. I'll get with you later today remind me if you don't hear from me by tonight :)

Customer: replied 1 year ago.
Nah ill rather have my refund because i feel Ive Wasted Money Here
Expert:  Lou P. master tech replied 1 year ago.

Fair enough. Take care. Hopefully you'll give us a shot next time. If you follow the customer service links you can process your own refund.

Customer: replied 1 year ago.
to let you know, my airbag lamp started to go On and OFF and is now completley OFF, all By itself .There Are some Stuff about mercs you still need to learn

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