Parts Catalog Accessories Catalog Tech Info Tech Forums
  Search our site:    
 Cart  | Project List | Order Status | Help    

Go Back   PeachParts Mercedes ShopForum > Technical Information and Support > Tech Help

LinkBack Thread Tools Display Modes
Old 08-13-2003, 09:41 AM
Registered User
Join Date: Aug 2003
Location: Livermore ,CA ,U.S.A.
Posts: 2
Controller Area Network problem

I need help with a alwas returning CAN code 41 and 173.
The codes reflect that the transmission goes in limp mode and doesn't shift out of second gear.This only happen when the ambient temperatur is above 85 degree and the vehicle has been driven for a longer distance,how long doesn't matter,and has been turned off and on again.
This problem puzzles me and I'm wondering if any one out there has some input for me.This is a ML 320 from 1998.

Last edited by Detlev; 08-13-2003 at 01:25 PM.
Reply With Quote
Old 08-13-2003, 11:37 AM
KAMAL's Avatar
Registered User
Join Date: Dec 2001
Location: Elk Grove, CA
Posts: 52
provide model & year of your car.

Kamal Atwal
2005 Triumph Bonneville T100 (Black/white) [Sold]
2007 GL450 (Dersert Silver)
2009 Toyota Corolla (Metallic Silver)
2002 Tundra V8 - 2WD (Desert Sand)
1995 MB E420 (Silver Smoke) [crashed, now resting in peace at Silverstar Recycling Center]
Reply With Quote
Old 08-13-2003, 05:51 PM
Gilly's Avatar
Registered User
Join Date: Mar 2001
Location: Evansville WI
Posts: 9,616
I assume the 2 codes are in ETC. Are there any other CAN codes besides these, such as in ME?
Has any work been done to the transmission?
Are there any codes for RPM sensors 1 or 2 in the ETC?

Reply With Quote
Old 08-13-2003, 06:18 PM
Join Date: Mar 2000
Location: Gainesville FL
Posts: 6,844
I worked a CAN problem in an ML and can tell you a number of things about its characteristics.

The first thing to do is to measure the resistance between CAN L and CAN H on the 16pin OBDII connector. The two wires are daisy chained between all the controll units (about seven if I recall) Where they go in on both LOW and HIGH there is high kohm resistance in the controller except for two terminator resistors of 120 ohms a piece. These terminator resistors are in the ME controller and the IC controller (Inst cluster). If the system is electrically right there will be 60 ohms across those two wires anywhere you care to measure it. But the easiest place is at the 16pin OBDII connector.

So to recap, if one were to take every controller that has CAN L and CAN H connections and measure the resistance across the two terminals while disconnected from the system one would get high kohm resistance on every one except ME and IC. Measuring these will give 120ohms each. Measuring anywhere from wire to wire there should be the resistance of two 120ohms resistors in parallel or 60 ohms.

The car I had would not shift and it had one of the wires CAN L or CAN H severed where the bundle passed from the electrical center to under the dash. Depending on what that first resistance is will determine what you are looking for. A shorted controlller, any controller would make the resistance less than sixty and interfere with communications. With a short just disconnect every controller till the resistance chnages.

My car had 120 ohms instead of sixty and I didn't at the time know where the terminators were. The I was reading was the IC which we found by disconnecting untill we had open circuit when disconnecting the IC. We still should have seen 120 ohms with the ME terminator engaged but one of the wires being broken left that side open.
Steve Brotherton
Continental Imports
Gainesville FL
Bosch Master, ASE Master, L1
33 years MB technician
Reply With Quote


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 Off
Trackbacks are On
Pingbacks are On
Refbacks are On

All times are GMT -4. The time now is 09:14 PM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2016, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2011 Pelican Parts - Posts may be archived for display on the Peach Parts or Pelican Parts Website -    DMCA Registered Agent Contact Page