Datalink Issue

I am trying to track down an active datalink problem with a 07 Volvo VN daycab with an eaton autoshift. I have checked several of the 1939 connections already, but before I go any further. I was wondering if there are any known troublespots in these tractors harness that causes the datalink issue. As a sidenote, it is active and one of its symptoms is when you turn the key off, it takes about 10 seconds for the engine to actually shut down. Also all of the ECMs on the tractor (ABS, Engine ECU, trans ECU and vehicle ECU) are responding to commands from the laptop and the onboard diagnostics.

Any help will be appreciated. Thanks

 

Volvo calls J1708 datalink (400-401 wires)

J1939 is called CAN

 

Any photos of these wires and connector, this is the same as you were saying on my post? Thanks again, Chad

 

MCFC connector (cab to chassis), find 400-401 twisted pair.

What diagnostic adapter do you use?

 

This may be so on some volvo models, but not all. Both the onboard and laptop are both saying the code is Datalink/J1939.

In addition a failed 1708/1587 wouldnt cause problems like I am having. It simply doesnt have control over what is happening. I am sure it is a 1939 failure. I am really just needing any possible help with any trouble spots in the 1939 harness. Thanks for any input.

 

Trouble spots, sure. Green and yellow twisted pair wires, run in from the firewall. I've seen alot of failures where the wires run over the steering column up into the fuse panel area. The datalink terminating resistor is up near the fuse panel, under the fuse panel is where all the modules are. Check all the wiring between them. Pin drag and whatnot in all the connectors. That's where I usually find problems w/ datalink on volvo's I see.

 

Green and yellow datalink and gray and orange J1939 CAN are European can marking, also used are blue and yellow (generally mercedes and DAF J1939). Yep, on some US versions Volvo used European markong, but from '99 Volvo uses black wires with figues in the USA and AU. so J1708 is 400-401 marked.

In EU Volvo use AMP connectors only, in the use AMP and Deutch

 

Thanks for the help. I ended up finding a broken wire on the drivers floorboard. It was for the shifter. It is connected through 1939. Thanks for your ideas. I hope if anyone else runs into a problem like this, this might help.

 

are wires were color marked? like on Volvo Cabovers?

 

The broken wire was the green wire from the green/yellow twisted pair. The other wires in the harness were all black, but are numbered like the rest of the tractor.