Parts Catalog Accessories Catalog How To Articles Tech Forums
Call Pelican Parts at 888-280-7799
Shopping Cart Cart | Project List | Order Status | Help



Go Back   PeachParts Mercedes-Benz Forum > Mercedes-Benz Tech Information and Support > Tech Help

Reply
 
LinkBack Thread Tools Display Modes
  #16  
Old 06-29-2005, 01:59 PM
Registered User
 
Join Date: Aug 1999
Location: Florida / N.H.
Posts: 8,804
< There is no connection to pin 14 on the 16 pin connector.
>>

Oh . did not know that..

No idea what they use for diagnostics on that ..
As far as the led , test the led/sw on you bat to confirm it is wired correct polarity.
That test is Red to bat pos, odd color to bat neg .. led should light

Red to bat +, blk to bat - , lamp should only light when sw is pressed..


< So I think we can rule out a wire problem.>>

Still need the requested info as to the same wires with a ground test .. if one is contacting ground or crossing to another wire , you can have a wire problem..
At the cost of ECU , I just want to check all the possibles closely

Reply With Quote
  #17  
Old 06-29-2005, 02:50 PM
Registered User
 
Join Date: Jun 2005
Location: UK
Posts: 66
Hi Arthur,
I had the LED the wrong way around
Tried again and got these codes from pin 8;
4 Hot film mass air flow sensor
9 O2S 1 (before TWC) - voltage too high, circuit open or voltage implausible
11 O2S 1 heater (before TWC) - Current too high/low or short circuit.
21 Ignition output 3 or ignition coil for cylinder 1 and 6
40 Transmission overload protection switch - open/short to ground or B+ or open or closed or
implausible

Reset them all, ran car for 30 secs and code 11 showed again (no other codes).

Rechecked the wire's resistance; Okay between earth and all other wires.
Reply With Quote
  #18  
Old 06-29-2005, 04:26 PM
Registered User
 
Join Date: Aug 1999
Location: Florida / N.H.
Posts: 8,804
< >>


You have cleared the codes , but I would like you to clear and reset the ECU .
After you clear ALL codes , you will get a single flash
When you get that , press led sw for 8 secs and then turn key off for 10 sec minimum. Now turn key on for 50 sec and then start car.
This resets ECU to norm base line . Run car for a day and then retrieve what the diagnostic module has stored...
A code 21 is in line with your T/3 circuit problem as I suspected and it is possible that you have a heat sink that has let go on that T3 circuit. Pretty common , according to the info I see..
Try it out and glad you got the polarity correct.
Reply With Quote
  #19  
Old 07-01-2005, 08:24 AM
Registered User
 
Join Date: Jun 2005
Location: UK
Posts: 66
Hi Arthur,
Got the 'new' ECU today and my misfire is gone.
I didn't want to drive it for a day with the misfire as I thought it might damage the cat.

I just wanted to say thanks for all the help.
Now that I know how to retieve the codes I'll keep an eye on it and see what happens.
Reply With Quote
  #20  
Old 07-01-2005, 09:39 AM
Registered User
 
Join Date: Aug 1999
Location: Florida / N.H.
Posts: 8,804
Great
Seems like these units are starting to cause problems now , specially with the dropping of the 2 cylinders cuz of heat sink seperation..

Did you get one from a Bone-Yard..??

http://www.carclinicmagazine.com/mercedes_common_ecu_failures.html


I would check that the primary ohm reading of all 3 coils are the same , as that could cause the same to happen to new ecu [ high draw].
I would also change all 3 plug connectors/resistors under each coil, as they are notorious for failure and poor contact. I personally believe they are where the load taxing of the ECU drivers has originated from day one......along with guys using plats .. use ONLY Bosch Supers/copper F8DC4 on this chassis/ w/104 engine..

Last edited by Arthur Dalton; 07-01-2005 at 09:49 AM.
Reply With Quote
  #21  
Old 07-01-2005, 10:04 AM
Registered User
 
Join Date: Jun 2005
Location: UK
Posts: 66
I got the part from a scrapyard, lotal cost £249.68 (about $462US) !
From your web-link..
Quote:
It is assential that the ignition coils are replaced as the new or repaired engine control unit will blow again if the old coils are left in place.
Poo! more money!

The plugs were Bosch super F8DC4. The ones I've just put in are Bosch super plus FR8DC+
Reply With Quote
  #22  
Old 07-01-2005, 10:14 AM
Registered User
 
Join Date: Aug 1999
Location: Florida / N.H.
Posts: 8,804
< >>

Don't want to rain on your parade, but those are resistor plugs and the resistors on that system are in the connectors already,.. you are doubling up on secondary resistance with them, and don't forget, these systems are 2 plug series circuit, so you are now adding two more resistors to the circuit.

I would not worry about the coils being changed if they ohm out good and uniform as much as i would worry about using Resistor plugs
Do a search on these and you will see testomonies that using the cheapo F8DC4 coppers are the best for 104 w/waste spark systems ..
.8mm [.032] setting/gap


Last edited by Arthur Dalton; 07-01-2005 at 10:46 AM.
Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Snap-On MT2500 KenP Tech Help 21 05-18-2008 12:47 PM
M104 cold-start problem back! ke6dcj Tech Help 0 08-02-2004 11:41 AM
Fan clutch - M104 on M119 anyone done it? moruzzi Tech Help 4 05-18-2004 06:04 PM
M104 Engine Longevity Question Sway Tech Help 26 12-23-2003 01:44 PM
anybody want to have a 190E M104 conversions Chiragp Mercedes-Benz Performance Paddock 10 05-10-2003 01:53 PM



All times are GMT -4. The time now is 12:58 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2024 Pelican Parts, LLC - Posts may be archived for display on the Peach Parts or Pelican Parts Website -    DMCA Registered Agent Contact Page