Free 7 Day Trial RV GPS App RV Trip Planner RV LIFE Campground Reviews RV Maintenance Free 7 Day Trial ×
 


Reply
 
Thread Tools Display Modes
 
Old 11-24-2021, 07:47 AM   #11
Senior Member
 
Scalf77's Avatar
 
Join Date: May 2007
Location: Beaverton, OR
Posts: 2,047
All those things could create problems, even change the resistance some, but not likely to give me those results

Mounting causing board flex, I am sure this board has spent a great deal of time going through extensive dynamics testing. I would suspect that they even use HALT (temp and vibration) in their design process. There could be a crack, but it would be manufacturing flaw.

These connectors are rock solid, I have inspected and cleaned. I went down a path of thinking water was causing an issue with one connector specifically.

A wire harness issue would also be a possible issue, highly unlike that it would show up as just this resistance issue.

The 42 ohms that I am reading in some ways defines possible issues. The termination for the circuit is suppose to be 120 in the PCM and 120 at the communication module. If we read the two 120 ohm resister in parallel we should get 60 ohms. (Bus should be between 54 to 66 ohm). If you were to add a second module with 120 ohm termination resister, with parallel resistance you would come in around 40 ohms. This is where MG's idea of finding the module and pulling off the resister comes from. I have been discussing issue with MG offline, initial thought was that an additional module was terminated on the bus.

Being that the PCM being isolated shows that the 60 ohm value is coming from it. Not really sure how it is laid out, but it is possible they use a split termination scheme ( 60 to 60 ohm in series with a cap to gnd in the middle). One could surmise that one of the resisters is shorted as a possibility.


-greg.
__________________

Scalf77 is offline   Reply With Quote
Old 11-24-2021, 08:03 AM   #12
REF
Senior Member
 
REF's Avatar
 
Join Date: Jan 2009
Location: Boulder, CO.
Posts: 2,233
Send a message via MSN to REF
Along those same lines, we purchased a Jeep 4xe and while we havenít had any problems, many have reported electrical related issues on the forums that shuts the vehicle down and lights up the dash, seems to stem from the wiring harness and faulty or bent pin connections during assembly
__________________

__________________
'03 Ford E350 7.3L Diesel
(de)SMB'd Custom RB-50
Quigley 4X4 w/Deavers & Agile Offroad's R.I.P. package
CCV High Profile Pop Top
REF is offline   Reply With Quote
Old 11-24-2021, 11:04 AM   #13
Senior Member
 
Join Date: Sep 2013
Location: Newberg, OR
Posts: 1,205
Quote:
Originally Posted by REF View Post
...seems to stem from the wiring harness and faulty or bent pin connections during assembly
Ah yes... the faulty or bent pin hypothesis.

I finally resolved an intermittent error code in the Allison trans in the Cummins van that seems to have been caused by poorly connected TCM terminals. I probed all of the female terminals in the connector and found that five (out of 85) pins were loose or very loose fitting (barely making a connection) with the mating terminal. two of the five pins happened to be related to a sensor that would fault and throw the code.

So yes...faulty or bent pins can cause problems. I haven't had the error since the connector repair.
mgmetalworks is offline   Reply With Quote
Old 11-24-2021, 12:24 PM   #14
Senior Member
 
Scalf77's Avatar
 
Join Date: May 2007
Location: Beaverton, OR
Posts: 2,047
All possibilities, I don't want to think of the hours of my life lost to hunting down bent pins in sockets. backplanes cables you name it. This goes from mainframes to servers, I've probably installed more processors and memory in a motherboard in one day, than most people will do in a lifetime. Ok maybe slightly exaggerated, in a couple of days.

I did give all the cable connection a good lookover, if my eyes were twenty years younger I'd feel more confident.

-greg
__________________

Scalf77 is offline   Reply With Quote
Reply

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 Off
Pingbacks are Off
Refbacks are Off

Powered by vBadvanced CMPS v3.2.3
Disclaimer:

This website is not affiliated with or endorsed by Sportsmobile SIP or any of its affiliates. This is an independent, unofficial site.


All times are GMT -6. The time now is 12:09 PM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2021, vBulletin Solutions, Inc.
×