Not cranking is an electrical problem. The fuel pump is not even in the picture yet. It sounds like you were running on just the battery and it ran down. That suggests there is a charging system problem. If I am right, use a portable battery charger to charge the battery at a slow rate for a couple of hours, then you will find the engine cranks just fine and starts right up.
Once the engine is running, you can use an inexpensive digital voltmeter to measure the battery's voltage to see if the charging system is working. You should find it to be between 13.75 and 14.75 volts. If you do, that only means it is okay to do the rest of the tests, but that requires a professional load tester. Your mechanic will have one of those.
If you find the battery voltage stays near 12.6 volts, the charging system is not working. At most, you can expect the battery to last for perhaps a half hour of driving as long as you do not use the heater fan, head lights, or wipers.
Here is a more-detailed description of the tests:
https://www.2carpros.com/articles/how-to-check-a-car-alternator
May 9, 2018 at 4:55 PM
