What should I do about my 2007 freigthliner columbia with

i am trying to figure out what you are calling the turbine. is it bolted to the engine? but attatched to the transmission?

As for the SM and the CH.

SM = System malfunction

CH= System self check..

Lets retrieve the fault codes.

Press and hold the Neutral button, and the FUNCTION button. All flash codes will steadily display in 1 1/2 seconds. Ignore the fault codes that flash. The TCU will list all the active codes on the instrument panel display.

When you are done pulling the codes, Release the neutral and the function buttons, turn the ignition off.

Cool!

Yuck, j1939 problems are tough.

The J1939 wires are green and yellow, you might have a bad terminating resistor, or a wire cut in the J1939 datalink.

Unplug the trans ECU, find the Yellow, and GREEN wire, they should be a twisted pair, they may be seperate in connector however. Follow this through the harness, it might be rubbed through somewhere, Freightliner has had trouble with the wire loom cutting into the wiring.

OHM these two wires out from Pin to Pin, Green to yellow, you should have 60 ohms. The resistor is located in the frame rail.

This makes sense, if the Trans ECU cannot see engine RPM or vehicle speed, it will not shift.

Does your dash guages work?, like oil pressure, Temp guage?, Tach?

If they do, this kinda rules out a locked up datalink.

If not, do the following steps.

You might also have something causing the datalink to lock up. You have several ECUs that are on J1939 that can lock it up.

If this was fleet truck, they most likely removed the Qual-Comm. If they removed the Satellite, alot of times they leave the wiring to the Satellite on the roof open to air, if this happens, they corrode up and can short out the wiring and also the datalink inside the plug.


I would start out by checking that, if that is not the case. Unplug the ABS computer, it is located behind the driver seat, in a panel on the side wall. Unplug all the connectors.

These are the ECU's on J1939.

Instrument Cluster
ABS computer
Trans ECU
Engine ECU
A/C controller, Bunk and Cab.
Vorad if it has it

Unplug each of these ECU's, Making the Trans ECU, and the Engine ECU the last ones. This gets rid of the possibilty of a data link lockup.

Let me know what you find.