1996 GMC Jimmy Turn the key and starter won't do anything

Hello and thanks for donating

What you have described is a failed ignition switch. You can run a temporary starter switch to fix this issue short-term. The primary fix is removing and replacing the faulty ignition switch.

That is correct. I have posted replacement steps below to help you if you choose to do this repair on your own..

Remove the column shroud halves.
Remove the column-to-dash attaching bolts and slowly lower the steering column, making sure that it is supported.
Remove the multifunction switch if necessary.
Remove the key alarm switch, if equipped by gently prying the alarm switch retaining clip with a small screwdriver. Rotate the alarm switch 1 / 4 in. (6mm) turn and remove.

WARNING
Extreme care is necessary to prevent damage to the collapsible column.

Make sure that the switch is in the LOCK position. If the lock cylinder is out, pull the switch rod up to the stop, then go down one detent.
Remove the two screws and the switch.

To install:

Before installation, make sure the switch is in the LOCK position.
Install the switch using the original screws. Tighten the screws to 12 inch. lbs. (1.4 Nm).
Install the key alarm switch, if equipped . Make sure the retaining clip is parallel to the lock cylinder. Rotate the alarm switch 1 / 4 in. (6mm) turn until locked in place.
Install the multifunction switch if removed.

CAUTION
Use of screws that are too long could prevent the column from collapsing on impact.

Replace the column. Tighten the nuts to 22 ft. lbs. (29 Nm); the bolts to 20 ft. lbs. (27 Nm).
Install the column shroud halves.

Sure I can help with that. You will want to use 14 gauge automative wire for the job, you can pick it up at any auto part store. You will also need the following :

push button starter switch
drill
wiring ends
crimping tool

Below are the basic steps for this temporary fix. Let me know if you need more assistance along the way.

Disconnect the vehicle battery negative cable from the battery.
Determine the best location for the push button switch. It should be in an area of the dashboard which can be easily reached by the driver.
Use an electric drill and a drill bit of sufficient size to drill a hole large enough to mount the switch. Check your switch for the size as it can vary from one brand to another.
Locate the starter solenoid which is built on to the starter itself.
Strip approximately 1/4 inch of insulation from one end of the 14 gauge wire. Using the crimping tool, crimp a solderless terminal (wire end) of the type necessary to fit the lugs on the back of your push button switch to the stripped end of this wire. Attach to the switch. Run the wire through the firewall and out to the solenoid.
Install a solderless terminal (wire end) which will fit the solenoid terminal to the wire and attach to the solenoid.
Fabricate a second wire and attach it to the switch. Connect the opposite end to a 12 volt power source or directly to the positive terminal of the vehicle battery.
Mount the switch in the dash board and reconnect the vehicle battery.

Now when you go to start the vehicle, you will still need your key. You only need to turn the key until the accessories come on and you hear the fuel pump kick in, do not attempt to crank the engine. Once the key is in this position, you will then push the starter button until the engine has fired up, then release the button. Now your engine should be up and running as normal.

Have you removed the plastic covers from the steering column? once the covers removed you should be able to see the screws holding the switch pretty easily

The lock cylinder is not the actual switch. The switch is behind the lock cylinder. Number 17 in the diagram I posted above is the cylinder. Make sure the steering column is lowered and the two should be 7mm screws/bolts

The purple wire