Datalink Issue

Heeelllllpppppp! I have a 07 Volvo 670 D12 and I need help with Data Link Disconnected. No anyone know what should I do. Do gauges work on the dash.

 

So my truck doesn’t have a Qualcomm fuse , does mean the has no suck thing as qualcom ?

 

So my truck doesn’t have a Qualcomm fuse , does this mean the has no such thing as qualcom?

 

#### I love this forum. Running through Tx panhandle in crazy rain. Got data link error and water/oil gauges off along with speedo and tach. Realized I had cut the thick wire running to the roof that went to the old fleet Qualcomm thing. Of course, open ended and WET!! Blew it dry taped it up and now everything working. Just wanted to say thanks

 

Hello masters, I’m having a problem with ( transmission ECU, transmission gears slector and engine ECU ) on my 2011 Volvo d13. I get these messages every morning before I go to work so I have to wait about 45 minutes to one hour until it disappears and then I could drive it. I took it to the Volvo dealer and they replaced the ABS module ($3200) and the radio plus it’s connectors ($2600) but the problem is not solved at all. Now they’re telling me it could be datalink issue. Can you please help!!? I really appreciated it!

 

You will not get far until you learn to go into the diagnostics on the dash and get the exact trouble codes. This is how you take control of the repair process.

 

Hi guys, I have a Datalink problem code J1708 / J1587 on my 07 Volvo VNL 670 with cummins . Truck is not derated to 62mpg and runs good however almost all gauges don't work other then fuel and air. Also I need to motion that sometimes they work sometimes not. When idling gauges may work for a few seconds and off, whan driving thy may work for few seconds or sometimes for minutes or hours and then not work minutes or hours. Usually change happens when I hit big bump driving. I've checked so far driver and passenger floor, for cuts and wire corrosion, I've swamped gauge cluster, checked QUALCOMM wires, checked wires along the frame under truck for corrosion. Also at the same time when gauges go out, steering wheel air bag light comes on and ABS light sometime. Any help would be appreciated. Also the reason I can't check more is i don't have a Wiring diagrams for this truck. If anyone has a Wiring diagram for 2007 Volvo VNL 670 please let me know.

 

The J1939 standard and J1587-J1708 standards are different. Data is transmitted throughout the vehicle on both of these standards, which are represented by a pair of green and yellow wires for the first standard and probably just regular black wires for the second. The green and yellow pair is capable of faster data transmission. I believe the older and slower standard (black wires) is what connects to many or most of your sensors. For example, your speed sensor, mounted at the back of the transmission. You will find that green and yellow pair surfacing in various spots around the vehicle and you should always make sure it's not rubbing on anything. Same for the other pair but it's harder to identify. You may have numbers on the insulation, say 325 on a wire connecting to a sensor. Well, you could trace that wire back by finding 325 again in a different spot but you won't get much help with the color coding. Searching for cut or rubbing wiring is often an exercise in futility but also often the problem. You might have some luck if your ECM is willing to give you a code leading to a bad sensor. A bad sensor can short out the two black wires going to it and therefore mute the entire sensor network. If you don't already know, you should be in park and use your stalk switch to scroll down to diagnostics and get your codes. Maybe you'll find them under engine ECU or vehicle ECU or whatnot. I'm not sure the ABS system connects to the data links. Maybe. But because your data link may be shorted, as in two wires touching, it might well be very difficult to pinpoint where they are touching because you can test anywhere on the network, front to back, and be shown they're shorted. The question, as you are finding out, is where. Yes, if you used to have a Qualcomm at the top of the cab in the rear, cut that cord and separate every single wire inside. Corrosion will turn into a copper oxide that shorts those wires. Maybe somebody else can come up with some ideas on typical places that data links are shorted at . . . One way to find the older data link is to search for a twisted pair of black wires, so that might help. Also, you can figure out where those wires should be based on knowing where all of the sensors are.

 

If it's help you

 

By the way, if there is a pair of datalink wires going to that steering wheel, you may already be getting told the problem.