Have you checked for any disconnected, damaged, or pinched wires? It's odd that there is something shorting, but none of the fuses are failing.
Also, does this only happen when the key is in the start position?
The A/C compressor/accumulator shouldn't have anything to do with the starter motor. Let me know.
I attached the wiring schematic below for the starter circuit so that you have a reference.
Let me know if anything as far as the wiring was moved, disconnected, or changed with the starter circuit. I have a feeling we have a pinched wire at some point.
See pic below.
Image (Click to make bigger)
Saturday, May 27th, 2023 AT 12:05 AM