When engine is turned off and keys have been removed, the radio and clock and interior electronics remain on. What would cause this?

Your car has several different ignition positions. They each offer slightly different functionality.
Off: In this position, the engine is off, and so are your electronic accessories (unless the delay has not expired yet). You can still turn on lights (headlights, interior lights, etc.).
ACC: This is the accessory position. Turn the key to ACC if you want to listen to the radio, play a CD or use other accessories without cranking the engine.
On: In this position, all of the electronics should come on. This is also the position that the key will return to after cranking the engine.
Start: Turn the key to this position to crank the engine. Let go of the key when the engine is running and the key will return to the on position.

http://www.aa1car.com/library/ignition_switch_positions.jpg

I use to own a car that had an ignition that was ACC - OFF - ON - START.

Try turning your ignition one position clockwise and see if the radio turns off and the key comes out.

https://hackadaycom.files.wordpress.com/2008/08/ignition.jpg?w=450&h=338

Is your clock part of radio assembly? There is usually a dimmer control for interior lamps, you rotate it to brighten or dim interior lamps--dome--instrument cluster--radio illumination. The same thing should work for the clock. If clock is part of radio assembly, I guess you can remove radio and dig into it, see if you find the wiring for clock illumination.

Blown fuse

Sounds like you have a short to power. there are several wires that connect to your radio and console . one is the ignition wire that kills power to the radio and console when the key turns off. What has probably happened is that wire has found a constant power source from another wire and it constantly stays on. finding this short is very difficult because it is under the dash so you might want to take it to a professional. Also if the van has the feature where the radio doesnt cut off until you open the doors, then your short may be somewhere in the sensors on the doors.

Usually the security light means it can't read the chip in the key.. the little black chip at the base of the key.
Try using a spare key

Telephone: Fax: VAT Registration No.:
Infrared remote control
NOTE: Infrared emitter can be seen at front edge of key.
System operation
Switch ignition ON. Ensure clock LED illuminates for 3-5 seconds. Pressing key lock button once activates central locking and alarm. Pressing key lock button twice within 3 seconds activates double locking system.
Programming
When
Key batteries completely discharged. Key batteries not replaced within 15 seconds. Key added or replaced. System malfunction.
How
Obtain all keys fitted with remote control. Turn ignition switch to position I. Wait approximately 10 seconds. Ensure clock LED illuminates.
NOTE: LED illuminates for approximately 5 seconds.
Switch ignition OFF and remove key, while LED illuminated. Programming mode activated for approximately 20 seconds (LED illuminated). Proceed as follows: Point key at receiver (located near interior lamp). Press and hold unlock button Fig. 1 [1]. After approximately 1 second key LED will flash once [3]. Press lock button 3 times Fig. 1 [2]. Release unlock button Fig. 1 [1]. Continue to point key at receiver until LEDs in clock and key have flashed 5 times. Ensure LED remains illuminated. Repeat above procedure within 20 seconds to program remaining keys. To exit programming mode and extinguish clock LED: Switch ignition ON and OFF. Wait approximately 20 seconds.
NOTE: A maximum of 4 keys can be programmed. Fig. 1
Radio frequency remote control
System operation
Switch ignition ON. Ensure clock LED illuminates for 3-5 seconds.


Pressing tailgate release button twice within 3 seconds unlocks the tailgate - if fitted. Pressing key lock button once activates central locking and alarm. Pressing key lock button twice within 3 seconds activates double locking system. Interior lamp illuminates when disarming system.
Programming
When
Key added or replaced. System malfunction.
How
Obtain all keys fitted with remote control. Fasten seat belts and close all doors. From position I, turn ignition switch as follows: To position II. To position I. To position II. To position I. To position II. To position I. Programming mode activated for approximately 20 seconds. LED or fog lamps ON warning lamp illuminates (some models) or the system will emit an acoustic signal to indicate start of programming mode. Proceed as follows: Type 1: Press and hold unlock button Fig. 1 [1]. Type 2: Press unlock button Fig. 2 [2]. Ensure clock LED or fog lamps ON warning lamp flashes (some models) or wait for acoustic signal (indicates correct programming). Wait 2 seconds. Repeat above procedure within 20 seconds to program remaining keys. To exit programming mode: Switch ignition ON. Wait 20 seconds.
NOTE: A maximum of 4 keys can be programmed.

wired up to the wrong power terminal

Radio will light up the clock works