How to replace the neutral start safety switch on a 2004 grand Cherokee 4.0

website https://big-manuals.com/products/copy-of-jeep-grand-cherokee-xj-yj-1995-workshop-service-manual

and this book helped me repair it within an hour, all by myself!!!! It's amazing, no hassle at all
From wiring diagrams, schematic illustrations, spark plugs info, parts info, stepwise in structions, torque specs, error/fault codes, engine info, to every single minute parts, you get everythingg in there you can't imagine how detailed it is

a/t (automatic)
is the PRNDL switch on the side of the trans. the N part, does that.

Your neutral safety switch needs replacing.Here's the part. Duralast Neutral Safety Switch CR401 2004 Jeep Grand Cherokee 2WD 8...

Either you got the wrong neutral safety switch or it is installed incorrectly

the switch is out of adjustment on its mount..loosen the mount bolts and readjust the switch..

Test/Service/Replace

The circuit on newer cars with automatic transmissions has a neutral safety, or neutral start switch installed between the ignition switch and the starter. The ignition switch cannot operate the starter motor unless the transmission is in park or neutral.
Late model vehicles with manual transmissions have a starter/clutch interlock switch that requires the clutch to be depressed to the floor.
Neutral Safety Switch
Normal operations of a neutral safety switch provides a quick check for the adjustment of the gear selector linkage.

• To do this, move the selector slowly until it clicks into the PARK position.
• Turn the ignition key to the START position.
• If the starter operates, the PARK position is correct.
• After checking the PARK position, move the lever slowly toward the NEUTRAL position until the lever drops at the end of the NEUTRAL stop in the selector gate.
• If the starter also operates at this point, the gearshift linkage is properly adjusted.
• This quick test also tests the adjustment of the neutral safety switch.
• If the engine does not start in either or both of these positions, the neutral safety switch or the gear selector linkage needs adjustment or repair.

CAUTION
Since you must work under the vehicle to adjust most shift linkages make sure you properly raise and support the vehicle before working under it. Also, wear safety glasses or goggles while working under the vehicle.
A voltmeter can be used to check the switch for voltage when the ignition key is turned to the START position with the shift lever in PARK or NEUTRAL. If there is no voltage, the switch should be adjusted or replaced.

Check the neutral safety switch,and the ignition switch,if the anti theft is not the problem.

It is located inside the transmission. As a DIYer I would highly recommend taking it to a transmission shop to have it fixed.

The switch is on the transmission..It is usually a dealer item but you can get one from Rockauto.com for about 1/4 of what the dealers charge.

OK then the switch is part of the gear selector switch on the side of the trans where the shift linkage hooks up. here is a picture and part number.
ACDELCO Part # C2241 $233.89