C0000 and P0701 Diagnostic Codes on 1998 Neon 2.0 SOHC Automatic: Causes and Fixes

I recently purchased a 1998 Neon 2.0L SOHC with an automatic transmission, which was towed home due to a failed head gasket—a known issue in early model Neons. The check engine light is on, and after connecting the OBD-II scanner, I received persistent C0000 and P0701 diagnostic codes. These codes cannot be cleared using standard scan tools. The C0000 code typically indicates a communication failure between the vehicle's ECUs or an internal system error, while P0701 points to a malfunction in the transmission control system, often related to incorrect input from the transmission speed sensor. Although a faulty speed sensor is a common suspect, I'm seeking expert insight into whether these codes are directly linked to the head gasket failure or if they stem from another underlying issue. Given that the head gasket repair may have affected engine and transmission communication, it's possible the codes are secondary symptoms. Can anyone confirm whether C0000 and P0701 on a 1998 Neon 2.0 SOHC automatic are typically caused by mechanical issues like a blown head gasket or sensor faults? What steps should I take to diagnose and resolve these codes? Thanks for your input.