I've had a 2006 S60 2.5t AWD Automatic for 8 years now, and just recently I've had the transmission go on it. I have replaced the transmission myself for an equivalent year and model Aisin AW 55-50 SN just recently.

The car was sitting for a few months in my driveway while I had the new transmission shipped in.

After the replacement and battery recharge, I was able to start the car and move it a few feet in Reverse. But a minute in after switching to Drive I lost power to the Gear Shift Module. When scanning, I received a U0103, Lost communication with the gearshift module DTC.

Currently, I have 2 issues:

1. U0103, no communication with Gear Shift module. Transmission does not engage gears, does not move, even when dash displays gear change.
2. Cooling fan does not turn on, even when the engine reaches temperature. No A/C, does not blow cold air.

I have done:

1. Recharged battery to 100%.
2. Checked all fuses, in all 4 fuseboxes (including the 60 amp fuse for the fan). All are good.
3. Reset TCM (by unplugging negative battery cable)
4. Gear position selector switch calibrated to correct position. I am getting visuals for switching between P, N, D, R, and the gear selector switch can be heard clicking into position.

What I can do:

1. Turn the car on, no problem
2. All other electrical components working, everything in the cabin is working.
3. I am not getting any other DCTs except U0103.

For the fan, I don't believe it's the coolant temperature sensor, anything else I can check? Could be fan motor, although I am getting power through the wires.

For the GearShift Control Module. Where is that located? Is it in the TCM next to the ECM?