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5K views 20 replies 6 participants last post by  oldiesel 
#1 ·
:eek Today while stop and go driving in town i saw warnings on the dash,Brake lining wear+ets+abs. I have seen these twice in the last couple of weeks on a cold start in the morning but as soon as i backed out of the yard they were gone.
Today when i started the car to leave McDonalds they came on and stayed on a couple of blocks later i was stopped behind a truck and suddenly had no drive forward or reverse.Having read alot on here i shut it off and restarted,after a couple of trys it engaged 2nd gear and since i was headed home began driving slowly at about 3500rpm w/speedo not working after about a mile or so it suddenly upshifted the warning lights went out the spedo came on and it behaved normally for 12 or so miles home.
I have not looked for codes yet but i only have an OBD2 scanner so probably will not read these other systems.
Any helpfull suggestions will be greatly appreciated. Does this sound like a brake light switch failure (i hope)
TIA Don :confused:
 
#4 · (Edited)
Got two codes ,P200 & p600 could not get my old autoenginuity on my laptop to connect at all,lucky a while back i put torque on the wifes little tablet it worked and found those 2 codes. according to a list i have p200 is "injector circuit malfunction"which i have had since i got the car and was told that cleaning the intake manifold should help,i have the gasket but hav not got around to do it yet. The p600 according to the list is "serial communication link malfunction" Hope someone has had experience with that one. TIA Don
 
#6 ·
Mr Boca
Thanks very much for your input,i wiil pull that K40 and resolder anything i can get at. Is it safe to remove that with the battery connected and the key out of the switch. Thanks again Don
 
#10 · (Edited)
.Mr.Boca
Following your advice i disconnected the ground cable,removed the K40 relay,opened it up up and examined it with good light and a powerful magnifing glass.All the solder joints looked normal so i resoldered all of them the tiny ones were not easy as i get pretty shaky doing things like that however the end result is everything is back to normal! Of course its a bit early to claim success as i only drove it around for about a half an hour.Thank you very much for your advice. Ill add afew pictures for those who have not had a K40 apart,easy job if you have any soldering skills. Don
 

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#12 ·
. . . examined it with good light and a powerful magnifing glass.All the solder joints looked normal . . .
I have more than the typical experience reflowing bad solder joints -- I have literally diagnosed and reflowed hundreds of them -- so I can say with some authority that if you didn't see cracked joints (which present as a dull ring around the through-lead), you didn't have one. With magnification, they are not subtle.

I think I've read that others have had faulty K40 module and not had bad solder joints, ie they had to actually replace the module to effect a repair.

Stretching a bit further . . . does the diesel version even have the failed K40-type failure? A few months ago ISTR trying to find an instance of someone reporting the K40 symptoms on a W210 diesel and fixing it via module replacement, and I think I couldn't find such an instance.

But most of you have more experience with W210s than I, so perhaps I just wasn't looking hard enough.
 
#14 ·
I have had very little experience with the 210 cars but based on the advice of others and the fact that i had success previously with a cruse control module on a 124 and the key fob on this car did the resolder on the K40 and now the car is back to normal so time will tell.The problem originally occurred as intermittent showing warnings on first startup in the morning and then acting normal all day so i am not going to call the resoldering a success for a while yet.If the problem comes back i will report it here.
Very possible that my inexperience with this type of repair that i overlooked a bad solder joint and fixed it anyway.I dont have any long trips planned and have AAA towing so i will continue using the car around home and see what happens. Don
 
#15 ·
Well it has been a week since the resolder job on the K40 relay circuit board and so far so good,no problems,no warning lights and no codes. Another couple of weeks and ill call it a success.any repair that costs nothing to do and only takes less than an hour and eliminates all those scary symptoms is a winner in my book! Don
 
#18 ·
The OBD2 system can read the "mapped" transmission codes from the ECM memory as P070xx series. The detailed transmission codes reading and resetting need a scanner that will connect to the 38 pin connector. Will this mapping supported for a 97 e300d ? Likely, but needs to be confirmed.
 
#19 ·
It has been 39 days since my solder repair and i have been driving the car every time i had to go somewhere including a trip to ft Lauderdale and back and its running just fine ,no codes,no MIL so at this point i will call it a successful repair and well worth the cost of a free repair.When i was working i would not have considered doing that on a customer car but for an old guy that still enjoys working on mechanical things i am reall happy with it. Don
 
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