So I have 2001 Hyundai Accent with snow balling electrical issues. So it all started when I simply took out the dome light and replaced it with a led bulb one night. The light wouldn’t turn on, try the old bulb and it wouldn’t work either. So in morning I tried to start the car and it wouldn’t turn over, thinking that the battery died I jumped it. Still nothing. The power locks would also not work anymore with the car not running. That night I rigged up a start button to the starting selinod so I could start and drive the car. All was good until winter time came. The car went to Canadian Tire to get winter tires put on. When we picked to car up the key was stuck in the ignition. I questioned them about it and they said they just put the key in and it wouldn’t come out. That night the battery went dead. With some investigating I found that the selionds that keep the keys locked in the ignition and the selinod that keeps the car in park when not running where drawing power, so i disconnected them. All was good for 3 months. Now there is a serious power drain. When at home and work I plug a battery charger in to maintain the battery. When driving home (12 minutes) the battery will go from 13.4v to 9.4v.

So I am wondering how to test the alternator on these cars (won’t run when disconnected)
any wiring diagrams anyone has and if anyone has had any of the above issues

 

Sounds like replacing the dome light with an LED started this snow ball effect
It blew out a fuse which then shorted out something else
First thing to do is check all the fuses and fusible links
If the radio doesn't work then it may have shorted out
Or blown a fuse. That fuse may be common to the power locks.
When the engine is running, power is applied through a different path

The key not coming out of the ignition was probably the gear selector not registering it was in park.

Simple test for alternator
Put multi-meter (DVOM) across the battery
With engine off, it should read around 12 to 12.5 volts
With engine running, it should read 14 to 14.5 volts
If not then need to trouble shoot alternator circuit before condemning alternator

 

if I remember correctly the switch to detect if it is park is above to the tranny? Under to intake and battery, if looked and tested the switch and it's working. Could this be a computer issue?

 

Check on You Tube for the Hyundai Accent Shop manual, which has the schematics. It's free.

Let's start by disconnecting the dome light, and look for a possible short circuit / wiring error. (UN-DO what you did when the problem started)

Connect a current meter between the car and the battery. Disconnect each circuit (pull fuses) one at a time. When you find the circuit that is draining the power, you can see it on the current meter.