HELLO MR.SLEEPWALKER,W220 sometime the ESP warning light on,I have changed the ESP CONTROL UNIT,if I ignition off the car,then ignition on the car is OK.

 

it sounds like a momentary voltage drop which is being recognize by ESP control unit. if the voltage goes below 8 volts, the light will come on and the fault memory is registered. the problem goes off after restarting the car because the system check finds it normal.

wht did you change the control unit anyway?

have you let them check the ESP wiring harness connector for presence of water or moisture? we have cases like this.

please have the fault memory read, and tell me the result.

i will give you further advise.

cheers.

 

THE CUSTOMER TOLD ME THE diagnosis show 'the esp control unit cannot send the signal to the CAN bus'.the dealer checked the wiring,then they let HE change the esp unit the number may be 031 545 09 32. SOMEBODY TOLD ME IT MUST BE CODING??
THE CUSTOMER TOld me AFTER CHANGE THE ESP UNIT ABOUT 100KMS THE CAR IS OK, WHEN HE DRIVE ON THE BAD ROAD ,THE ESP WARNING LIGHT ON.THEN THE CAR LOSE THE POWER.THE THROTTLE HAS NO RESPONSIBLE.HE CHECK THE ABS SENSOR OM IS THE SAME.
may be some wiring connects?yaw sensor?B24-2 ?
PLEASE GIVE ME SOME ADVICES THEN I WILL CHECK THE CAR BY MYSELF.

 

are you the mechanic?

as of now i am still on weekend rest, and all the information is in my office. i will answer your questions on monday.

give me the chassis number or VIN of the car so i will know what we are going through.

was ABS and ESP light is on together or just ESP?

check the actual value of the yaw rate sensor by shaking the car. it should be fluctuating.

if it works fine for the first 100km after replacing, then it doesn't need coding anymore because the other control units have already recognize that there is BAS, ESP control unit installed. some of them are already ready to install. if the ESP lamp is blinking and not steadily on, then a coding must be performed.

if the wheel speed sensor is faulty, a fault code will register.

is the problem present all the time now?

the ESP can control the throttle valve, and this is the reason why it get no response from the pedal.

as i said, the wiring or connector must be corroded, so pay very much attention to it patiently. don't just look at it, see the pins until you feel contented.

pull out the other control units also such as ME (engine), and EGS (transmission). they are side by side on the right. look and check for any oil contamination (oil contamination disrupts CAN). don't let anything escape your diagnosis, and you have to be very carefull in checking. do it professionally (like me ).

 

Thanks ,MR sleepwalker.
I am not a professional mechanic,but I am interested in repairing mercedes.It MEANS TO me a challenge. sorry for my poor English.I am chanese,I think you may stay in china sometimes ago.
the customer told me the ABS.SPS.ESP warning light on at sametime.
I will send the correct VIN number to you.
The mechanic told me before he changed the ESP unit the light on frequency if he often use the brake,at that time I think may be the sensor on the brake booster
not very good.can the diagnosis detect the faulty code? the car was checked in mercedesworkshop in HANGZHOU,(you know it because i know you ever worked at ESTEN STAR SHANGHAI WHEN APEC ) THEY told him the esp unit must be changed.
Tomorry i will send you the damage code obd2,I haven't the STAR diagnosis,is this also useful to you?
I will check thE esp wiring connector,i think you are right,after he change the unit,he drive the car on the highway for about 100kms,the car is ok .then he drived on the bad road, the warning light on.

 

so you are in china? in hangzhou? your english is not bad because you can write in english... very rare for locals.

yes, i work for eastern star in shanghai and in charge of sensitive problems on all the eastern area of china. i am in wenzhou now, but not working on wenzhou star because i don't want to. i prefer doing bmw and mercedes-benz at the same time because i can always get a few more step higher than others when it comes to technology.

don't call me mr. sleepwalker, it's just a forum alias. i'm alfonso, and they all know me all over china... mercedes-benz or bmw. hangzhou benz used to be under my area of responsibilty too.

tell me your name, exact location and telephone number.

if it is the travel sensor on the brake booster which is faulty, the BAS lamp will give you a fault code. check that travel sensor if it has a blue dot on it (modified parts).

if you can speak english, call me.

my number: yao san wu liu liu er liu yao ba chi ba.

 

MR AIFONSO,I had heard your name from my friends which also work at eastern star
XIAMENG benz.he know you.I KNOW JOY,LENEI ALSO philippines in hangzhou benz.
because I had worked at that company several years ago.
Why do you work in wengzhou? I am in hangzhou.I am a dealer for B&B PARTS.
MY MOBILE NUMBER IS 13606643574 OFFICE MUNBER IS 0571-86434983