CAN C DIAGNOSTIC HELP

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wegner426
Newbie
Posts: 2
Joined: Wed Oct 10, 2018 2:19 am

CAN C DIAGNOSTIC HELP

Post by wegner426 »

Good evening. new PICO Scope user here, looking for a little advice.

Working on a 2013 Ram 3500 Pickup truck. CAN system uses a wiring layout with 2 junction blocks or "STAR Connectors" connected by a jumper harness between the two. Each STAR connector has 10 or 12 connectors where dedicated CAN C wiring runs from the modules to the STAR connectors.

I have an intermittent issue where the CAN network is going down, and it doesn't last long when it happens. Multiple modules setting CAN C performance codes and loss or Comms.

Typically this can be resolved by removing modules from the STAR connectors until comms are restored, then you know you have a faulty module or CAN wiring between STAR connector and module.

Unfortunately this issue car doesn't stay broke long enough for me to complete the process. Took approximately 80 miles today to malfunction and wouldn't stay down long enough when it did.

I have checked the vehicle over head to toe looking for a harness short or rub through and cannot find anything.

I have attached a couple files I managed to save of the issue if anyone can look at the files. Some parts of the file looks like it is shorting to ground although the voltage doesn't appear to drop all the way to zero.
Attachments
2013 Longhorn.psdata
(3.18 MiB) Downloaded 326 times

liviu2004
TwoWaves
TwoWaves
Posts: 472
Joined: Sat Mar 19, 2016 8:23 am
Location: Netherlands

Re: CAN C DIAGNOSTIC HELP

Post by liviu2004 »

So like wiring harness shorts to ground somewhere, but not long enough. I suspect you run the wiring harness jiggle test and found nothing.

wegner426
Newbie
Posts: 2
Joined: Wed Oct 10, 2018 2:19 am

Re: CAN C DIAGNOSTIC HELP

Post by wegner426 »

Correct, will make another pass at it today. Attached is the other file, both have issues if you page through them.
Attachments
2013 Longhorn2.psdata
(3.23 MiB) Downloaded 343 times

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