98 ford expedition xlt replaced key cylinder it cranks but no start.at bottom of steering column is a box with wiring.need diagram.I think or ???

You'll need a new lock cylinder, starter switch module, and either a replacement steering column wiring harness or a box full of crimp connectors to patch the wiring back together. Before you patch the wiring, make sure it will still fit in steering column when you're done; it's usually a rather tight fit to begin with. Your best source would be a salvage yard. Check car-parts.com to see who has these parts available (the lock cylinder will either have to be rekeyed by a locksmith to fit your existing key, or you'll need to get keys with it).

There is no such thing as an underhood wiring diagram. Wiring diagrams are grouped by SYSTEM, not location. So you'd have to get separate wiring diagrams for the charging, fuel injectors, sensors, lights, etc. Even then it's difficult to get the exact diagram. Read this post on what's involvled.

http://ricksfreeautorepairadvice.com/get-car-wiring-diagram/

Check the sensor ring on the column that's around the cylinder for a bad wire and check the receiver plug and antenna also check your key if it has a battery and the fuse for the pats system download the manual from ford owners. Com and go to roadside emergencies and your fuse box diagrams are in there and the fuse values and relay locations something is loose or corroded clean all associated with the pats system and write everything down that you did so things can be ruled out also check the column wire connections all the way down to the floor

Can you be more specific?
Is there a component that is wired through the steering column that has a problem? Turn signals--horn--cruise control--whatever, I need more info?
I don't believe I have an over-all wiring diagram for steering column, itself?

That box is for the anti-theft system , he changed the lock cylinder . You need new PATS keys . PATS - passive anti theft system .The transceiver module communicates with the encoded ignition key. This module is located behind the steering column shroud and contains an antenna connected to a small electronics module. During each vehicle start sequence, the transceiver module reads the encoded ignition key identification code and sends the data to the instrument cluster.
And the dealer is the only one that can program the keys . or a mobile lock smith .

When you start it up don't completely release the key from the crank position, let off just enough to stop the starter, if the engine continues to run the ignition switch is defective, a common problem in this year. This is not the lock cylinder but the electrical switch located down at the bottom top of the steering column that the ignition key cylinder actuates via a long steel rod.

SECTION 211-05: Steering Column Switches 1998 Expedition/Navigator Workshop Manual REMOVAL AND INSTALLATION Procedure revision date: 02/11/2000 Multifunction Switch Removal

1. Disconnect the battery ground cable (14301).

1. Remove the ignition switch lock cylinder (11582).
   1. Insert the ignition key into the ignition switch lock cylinder and turn to the RUN position.
   1. Insert a punch through the hole in the lower steering column shroud and push the ignition switch lock cylinder release tab while pulling out the ignition switch lock cylinder.

1. Twist the tilt wheel handle and shank (3F609) and remove.

1. NOTE: Move gear selector to lowest position to access steering column opening cover.
   Release the four clips and remove the steering column opening cover.

1. Remove the upper and lower steering column shrouds.
   1. Remove the three screws.
   1. Remove the lower steering column shroud.
   1. Remove the upper steering column shroud.

1. Remove the multi function switch.
   1. Remove the two screws.
   1. Disconnect the electrical connectors.
   1. Remove the multi function switch.

Installation

1. NOTE: When the battery (10655) is disconnected and reconnected, some abnormal drive symptoms may occur while the vehicle relearns its adaptive strategy. The vehicle may need to be driven 16 km (10 mi) or more to relearn the strategy.
   To install, reverse the removal procedure.

This is a common problem for the turn signal switch itself. Try used. You will notice in the instructions to remove the steering wheel. Don't. The removal of the ignition switch is also not necessary. Remove the screws at the bottom of the column where it shows and take a screw driver and pry the other side up to see the 2 screws (torx, or star bits) to remove. This will only take about 20 minutes to perform.

1. Disconnect the negative battery cable.
2. Remove the 4 retaining screws from the lower column shroud and remove the upper and lower shrouds.
3. Remove the 2 retaining screws from the multi-function switch and unplug the 2 wiring connectors.
4. Remove the switch.

To install:

1. Install the multi-function switch.
2. Tighten the 2 retaining screws and attach the 2 electrical connectors.
3. Install the upper and lower column shrouds. Tighten the 4 retaining screws.
4. Connect the negative battery cable.

F-150, F-250, Expedition, Navigator and 1999-00 Super Duty Models

Fig. Fig. 1 Turn the ignition switch to the RUN position and push the lock cylinder release pin with a suitable punch while ...

Fig. Fig. 2 ... pulling out the lock cylinder

Fig. Fig. 3 Remove 3 steering column shroud retaining screws and ...

Fig. Fig. 4 ... remove the upper and ...

Fig. Fig. 5 ... lower steering column shrouds

Fig. Fig. 6 Remove the switch retaining screws, lift the switch assembly up and ...

Fig. Fig. 7 ... detach the switch electrical connectors to remove the switch

1. Disconnect the negative battery cable.
2. Remove the ignition key and tumbler as follows:
   1. Turn the ignition switch to the RUN position.
   2. Push the lock cylinder release pin with a suitable punch while pulling out the lock cylinder.
   
   
3. If equipped, twist off the tilt wheel handle and remove.
4. Remove 3 steering column shroud retaining screws and remove the upper and lower shrouds.
5. Remove 2 self-tapping screws that retain the combination switch to the steering column casting. Disengage the switch from the casting.
6. Detach the electrical connectors, being careful not to damage the locking tabs and the shift position indicator cable.

To install:

1. Connect the combination switch electrical harness connectors ensuring that the connectors are fully engaged. The wiring for the switch is to be routed under the shift position indicator cable.
2. Install the combination switch with 2 self-tapping screws. Tighten to 19-25 inch lbs. (2-3 Nm).
3. Install the upper and lower steering column shrouds. Install the retaining screws and tighten to 9 inch lbs. (1 Nm).
4. If equipped, install the tilt wheel handle ad tighten to 44 inch lbs. (5 Nm).
5. Install the ignition key and tumbler assembly.
6. Connect the negative battery cable.
7. Check the steering column and combination switch for proper operation.

autozone.com sign up its free then click on repair manuals you will find all of your info there....good luck

http://www.installdr.com/Harnesses/Ford-Wiring.pdf hope this link helps. Good luck. Keep me posted.