Engine will not start, and HDS does not communicate with the ECM/PCM (MIL comes on and stays on)

Engine will not start, and HDS does not communicate with the ECM/PCM (MIL comes on and stays on)

Engine will not start, and HDS does not communicate with the ECM/PCM
(MIL comes on and stays on)

Troubleshoot the ECM/PCM power and ground circuits ECM/PCM Power and Ground Circuit Troubleshooting.

Also check for

No power to ECM/PCM

Also check for

No ground to ECM/PCM

Also check for

Short in reference voltage circuit