Keyless entry is not working

Have you got the valet switch turned on?

Check trunk release solenoid for power and ground when applied from switch. If power and ground ok, then release solenoid is the problem in the trunk lock mechanism. If misssing power or ground, then electrical diagnostics will be required

Use your key to unlock the door / trunk. If your car starts up; it might just be a connector and / or your battery in your remote. Try the simple / cheaper fix check by checking the connectors leading to the trunk release solenoid.

Here you go. I think this may be what you are looking for. I hope this helps and good luck.

1994 Mercury Grand Marquis Alarm, Remote Starter, Keyless Entry Wiring Information Constant 12V+ Yellow Ignition Switch Harness Starter White/Pink Ignition Switch Harness Ignition Red/Light Green Ignition Switch Harness Accessory Gray/Yellow Ignition Switch Harness Tach Gray/Orange EDIS Module Brake Switch Light Green Brake Switch Trunk Release Purple/Yellow Driver's Kick Panel Trunk Pin Brown/White (-) Light in Trunk Parking Lights Brown Light Switch Head Lamp Red/Yellow Light Switch Hood Pin n/a Factory Disarm n/a Door Trigger Black/Light Blue Driver's Kick Panel Door Lock Pink/Yellow Behind Glove Compartment w/Keyless w/o Keyless (-) Door Unlock Pink/Light Green W/o Keyless Reverse Polarity Horn Wire Yellow/Light Green (-) Steering Column Windows Up LF=Yellow, RF=White/Yellow, Windows Down LF=White/BlackRF=Tan/Light Blue

i honestly am guessing,can you turn key to the left from vertical or right from vertical,if so one (left or right)is to lock trunk so you can give your keys to valet parkers....

disconnect battery for 10 minutes.

security module in the trunk ???? There is no security module in the trunk . What light's come on by them self ? Park lamps , headlamps , brake lamps ,turn signals etc.... The module for anti-theft is under the right hand side of the dash . The remote keyless entry module is located in the trunk. Is this the part you hear clicking in ?
Door Lock Control Processor, Electronic NOTE: The electronic door lock control system will not function when the ignition switch is in the RUN or ACC position.
The electronic door lock control processor:

• is located on the LH side of the luggage compartment.
• contains a radio receiver that receives a signal from the keyless entry remote transmitter (15K601) through electronic door lock control processor antenna, and sends the appropriate command to the power door locks, the horn relay, the indicator flasher, or the anti-theft warning system.
• is equipped with a battery backup which holds the programmed code in memory in the event the vehicle battery is disconnected.
• • Doors Do Not Lock or Unlock Using Keyless Entry Remote Transmitter
  • Circuit.
  • Electronic door lock control processor.
  • Keyless entry remote transmitter.
  • GO to Pinpoint Test B .

The keyless entry matches to the module for it that is mounted under the dash. It may have gone bad since your remote will not function. Of course it could be your remote as well that went bad

stand at the vehicle and push and hold the lock and unlock buttons till the horn chirps to resync the key fob

Same car same problem, but I found the plug w/two wires behind the glove box. It is on a brace on the left hand side, has a clip holding it there. Lift up on the clip and it slides off.
I jumpered those two wires, the door locks did not cycle as was in the instructions and remote still doesn't work.
Sounds to me like I'm missing power from somewhere, but where?
Hope you find your wires and they work for you.