Not sure where to start. 2012 Transit Connect NO CRANK

[CleanTruck]

Hey everyone, hoping someone can point me in the right direction as I'm not very adept in troubleshooting. I was told by mechanic I will need to get the PCM replaced and wondering if this is the right solution since I do have multiple error codes apart from PCM.

What do you guys recommend I go about checking first? Wiring, Relays, Fuses?

Also what is the wiring underneath the driver seat for? I see some cables disconnected and just out and about not plugged in or tucked away.

Here are the codes that FORScan shows:

1. PCM P1000 - OBD Systems Readiness Test Not Complete
2. PCM P1260 - Theft Detected, Vehicle Immobilized
3. PCM P1635 - Tire/Axle Out of Acceptable Range
4. ABS U0401 - Invalid Data Received From ECM/PCM 'A'
5. IC U2511 - CAN communication bus fault
6. IC U2199 - Invalid data for Engine Coolant
7. IC U2510 - Invalid or Missing Data for Vehicle Security
8. VSM B2872 - Tire Pressure Sensor Fault
9. VSM U2023 - Fault Received from External Node
10. GEM/SJB B1318 - The battery voltage level is too low.

Also ran PCM self test and these popped up:

===DTC P0108:00===
Code: P0108 - Manifold Absolute Pressure/Barometric Pressure Sensor Circuit High

Module: Powertrain Control Module===END DTC P0108:00===

===DTC P0113:00===
Code: P0113 - Intake Air Temperature Sensor 1 Circuit High Bank 1

Module: Powertrain Control Module===END DTC P0113:00===

===DTC P0443:00===
Code: P0443 - EVAP System Purge Control Valve 'A' Circuit

Module: Powertrain Control Module===END DTC P0443:00===

===DTC P0453:00===
Code: P0453 - EVAP System Pressure Sensor/Switch 'A' Circuit High

Module: Powertrain Control Module===END DTC P0453:00===

===DTC P1289:00===
Code: P1289 - Cylinder Head Temperature Sensor 'A' Circuit High

Module: Powertrain Control Module===END DTC P1289:00===

===DTC P1635:00===
Code: P1635 - Tire/Axle Out of Acceptable Range

Module: Powertrain Control Module===END DTC P1635:00===

[CleanTruck]

Not sure if it's related but I only have one physical key and no other PATS / Remote Car Key

[craigb]

check for 5v reference at the map sensor. Possibly loss of 5v on shared circuits. check wiring schematic.