Hello. first time posting, but these threads have helped me solve many issues, so thank you.

I have a cold no start that began spontaneously Sat morning. When I turn the key to run, there's some ticking sounds coming from the fuse box area under the steering wheel, the dash lights look like the coil is heating normal, then the sounds change, the check engine light comes on, the coil light blinks once and vanishes. I turn the key. The engine cranks for 4-5 seconds, then make a grinding sound that might be grinding, might be a loudly buzzing electrical part. As many times as I try, it cranks, but won't turn over.
With the key in run, I pulled the fan belt and contacted the starter cable to the positive battery terminal... it cranked and cranked... no turning over.
I have a little harbor freight code reader, and the codes it shows are 7e8 and 7e9. Both batteries are 2 years old, read 12.4, and they passed the test at autozone. Battery and starter connections are clean. Starter was replaced in June 2021
My truck is parked facing uphill. It gets about 30-40 degrees at night. Thanks for any help.

 

Your code reader is adequate for the task ahead of you.
Download the Forscan app and get a wireless adapter for,the obd2 port of the vehicle. That combo will read sensors and codes.
Then watch this and post your results

 

Alright, Forscan looks a bit different than torque pro. Here is all the info on the errors page:

===TCM DTC ===Successful DTC reading, no error codes found

Module: Transmission Control Module
===END TCM===

===PCM DTC P0603-60===
Code: P0603 - Power interruption on KAPWR circuit.

Status:
- DTC Present at Time of Request
- Malfunction Indicator Lamp is Off for this DTC

Module: Powertrain Control Module

Diagnostic Trouble Code details

Power interruption on KAPWR circuit.

Open KAPWRcircuit.

Loose/poor battery connections at the battery and engine block.

This DTC may be caused by :

If a recent PCM disconnect or battery disconnect is suspected no action is required unless the code continues to appear after being cleared.

Reprogramming can cause this code. If reprogramming was done clear codes and release vehicle.

Improper connection


===END PCM===

===PCM DTC P1000-60===
Code: P1000 - On-Board Diagnostic (OBD) Systems Readiness Test Not Complete

Status:
- DTC Present at Time of Request
- Malfunction Indicator Lamp is Off for this DTC

Module: Powertrain Control Module

Diagnostic Trouble Code details

On-Board Diagnostic (OBD) Systems Readiness Test Not Complete

Follow the routines in the service manual to resolve the DTC listed.


===END PCM===

===PCM DTC P2617-E0===
Code: P2617 - Crankshaft Position Output Circuit / Open

Status:
- DTC Present at Time of Request
- Malfunction Indicator Lamp is On for this DTC

Module: Powertrain Control Module

Diagnostic Trouble Code details

Crankshaft Position Output Circuit / Open

This DTC may be caused by :

Open circuit.

 

Try cranking (rotating the engine) with the starter solenoid jumpered to the passenger battery + terminal and see if you hear any grinding. Do it on a cold engine and with the key off.