Volvo Fault Question

I have a 2007 Volvo VN series truck with the D12 engine and Meritor 12 speed Auto Trans. The truck has 618,000 miles on it. In the Diagnostics menu, I pulled the fault codes from the Vehicle ECU and received the following with an occurrence rate of 255 times: (MID144 SID231 FMI2) with the heading "J1939 Data Link Fault".

From the Transmission ECU I received a J1939 Data Link Fault with 4 occurrences.

From the Brake ECU, I received a J1939 Data Link Fault with 5 occurrences as well as a Power Supply fault (MID136 SID251 FMI3) with 25 occurrences.

The truck keeps giving the "SM" on the dash readout and the truck will stay in one gear without shifting up or down, and this usually causes the engine to stall. The ZF Meritor technician that I spoke with on the phone said that the transmission is going into Manual Shift mode, and he said it could be anything from a sticking Brake Switch to and ABS module problem to anything at all. He said you have to have the computer with the relevant software to really get to the heart of the problem. The active code that my driver retrieved while the "SM" was displayed was "E7". Inactive codes were "37, 91,92". I know that 37 refers to the clutch actuator, not sure about 91 and 92.

Last week, I replaced both Camshaft/Crankshaft sensors because the Diagnostics menu showed multiple faults and the engine turned over too much before starting, so that problem is fixed.

Any info would be appreciated.
Thanks