I have three of these lifts, reach 740-R35TT serial numbers 250, 251 and 252(sister machines). I have one lift that was giving and intermittent code 57 for about 2 to 2 and a half days/shifts. It finally became a solid code and now is a dead machine. In the service manual it says the display module is recieving no communication from the VM. I ran the test checklist from the service manual (test I23 CAN BUS). All tests but one pass. The one test (test 3) that fails says to test the wires. The wiring tests good. 0.5 Ohms. It says if the wirinig is good then replace the LA (Lift Amplifier). So what I actually did was took the lift amp out of my dead machine and installed it in one of my live trucks. Works just fine in the live truck. When I take the VM out of my dead truck and install it in the live truck. Code 57 follows that VM and conversly when I install the VM from the live truck to the dead truck I don't get Code 57 but I get codes 5G and 5J.

Any help would be greatly appreciated.