Trouble with Cat C15 Acert

Hello all,

As the title states, I'm having trouble with a Cat C15 reman that our shop decided to buy and install.

The first issue is that I can't figure out which wires from the main engine harness go where on the starter The labels that were in place one the respective wires tore off because we had washed the compartment, unfortunately.. Two white wires splice into one connector (wire A in the picture), which has 12 volts when the key is on, and another wire which looks to be yellow (wire B) has just over 7 volts when the key is on, and a third wire (wire C) is dead, so I assume that one goes to ground.

The second issue that we are having is that since the wires were probably hooked up wrong and we tried to start it, we aren't getting any reading from the ECM with our scan tool. The fuse in the battery box is good, and I can only assume that is the only fuse for its. The truck it is in is a 2005 Freightliner classic, which doesn't seem to have ANY fuses, just a breaker block and relays behind cover in front of the shifter. I haven't been able to locate any kind of diagram for this truck, either. A few of the relays aren't labeled.

I have been searching for any information on this particular setup for weeks now, and it seems as if I am on a wild goose chase. Second other pictures are for any reference anyone may want. I really appreciate any assistance you all could give.

Thanks!

2005 Freightliner Classic
Vin: 5DU34316
Cat C15 Acert
Serial: MXS16849