resetting the computer?
Thread Starter
Senior Member
Joined: Oct 2006
Posts: 356
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From: Glendale, AZ
'95 E420 SE
resetting the computer?
I did a search on this, but couldn't find anything specific to the W124. So, here goes:
I have a '95 E420. This weekend, while cleaning it I sprayed down the engine with soap and water to rinse the dust off. The car had sat all night, so the engine was cold. Much to my horror however, when I went to start the car a few hours later, the engine is now only running on four cylinders (my guess...I really don't know how many or how few). Logically it would seam as though I have somehow corrupted one of the rotors, but that is my best guess. I pulled thecenter covers to expose more of the mechanicals....everything looks bone dry. I have checked every connector i can find....they all appear dry and tight as well.
So, I have three questions:
1) will a data link tell me what is wrong?
2) can you reset the engine computer by disconnecting the battery or does it need to be done through a computer?
3) is it built into the programming that if the car gets too hot it will automatically shut down half the cylinders in an effort to reduce engine temperatures? If this is the case, would I see a check engine light?
Thanks in advance for any help I can get.
I have a '95 E420. This weekend, while cleaning it I sprayed down the engine with soap and water to rinse the dust off. The car had sat all night, so the engine was cold. Much to my horror however, when I went to start the car a few hours later, the engine is now only running on four cylinders (my guess...I really don't know how many or how few). Logically it would seam as though I have somehow corrupted one of the rotors, but that is my best guess. I pulled thecenter covers to expose more of the mechanicals....everything looks bone dry. I have checked every connector i can find....they all appear dry and tight as well.
So, I have three questions:
1) will a data link tell me what is wrong?
2) can you reset the engine computer by disconnecting the battery or does it need to be done through a computer?
3) is it built into the programming that if the car gets too hot it will automatically shut down half the cylinders in an effort to reduce engine temperatures? If this is the case, would I see a check engine light?
Thanks in advance for any help I can get.
Last edited by ShanMan; May 21, 2007 at 03:34 PM.
Senior Member
Joined: Apr 2007
Posts: 352
Likes: 91
My opinion:
1) Maybe. You would likely just see misfire faults.
2) Likely. Leave the battery disconnected long enough to drink a beer or two.
3) No.
I think it is likely you got water into one of the ignition caps or down the spark plug holes.
1) Maybe. You would likely just see misfire faults.
2) Likely. Leave the battery disconnected long enough to drink a beer or two.
3) No.
I think it is likely you got water into one of the ignition caps or down the spark plug holes.
Thread Starter
Senior Member
Joined: Oct 2006
Posts: 356
Likes: 0
From: Glendale, AZ
'95 E420 SE
Thanks for the reply. I talked to an MB service tech today...and he told me that the computer can only be reset using a DOS (DAS?) tester. I assume that is the data link. I agree that I got something wet. Odd though considering I have had the engine up to 80 degrees celsius twice and it's been three days of over 100 degrees here. Wouldn't you think it would dry out by now?
Hopefully resetting the computer will fix that problem. No matter, it goes in tomorrow for an oil change and all new coolant hoses. I guess I'll know soon enough. Thanks again.
Hopefully resetting the computer will fix that problem. No matter, it goes in tomorrow for an oil change and all new coolant hoses. I guess I'll know soon enough. Thanks again.
