IMO one should always use a remote starter switch or jumper wire instead of a screwdriver or pliers.

The arcing can cause a starter relay to go bad.

Always have the battery fully charged with battery charger before trying to diagnose electrical problems.

Battery Cables themselves can corrode underneath the insulation causing continuity problems


If the starter won't crank using the method pictured below.

Try a booster cable from the battery post to the starter lug directly