Trunk release works as intended when ignition is off and remote is used. when trunk is closed and ignition key is turned on, trunk opens and latch keeps clicking until key is turned off.

Hello James Squyres,

Of the 33 TSBs (tech service bulletins)...

I found nothin on your issue...

Going to the vehicle drawings... (I'm guessing you are considering keeping this beauty)...

Get the FACTORY+WORKSOP+MANUAL... I HIGHLY
recommend for drawing (exactly this issue) and easy secrets to get through those nasty UNIQUE Caddy tasks.. that NO body but your friendly CADDILAC Club might ALSO know...

Nevertheless...
your drawings are presently available on one of my favorite sites "BBB Industries: (see below, registration required).

Perusing the drawings...
The only source not shared with your manual ignition source appears to be through your "TRUNK RELEASE" function.. is sourced (without the ignition) through "THE TRUNK LID LATCH SWITCH"... (ground source).

I am thinking LATCHED (totally defective, replace) contacts there would cause your problem...

BUT... on further consideration...

The drawing show a total TRAVEL of the un-latched lock should completely open the ground circuit... reversing POLARITY of the motor and ready it for the LATCHING sequence...

To me...

It looks to be the trunk lock TRUNK-LID PULL DOWN MOTOR STRIKER SWITCHES... failing to release (change polarity) in the UP position...

Replace the "TRUNK-LID ADJAR" switch.
Everything SHOULD come up peaches...

As to why it is not an issue with manual control...
I'd need to be there with a Volt-Ohm Meter

(perhaps we could dialog)...

Happy hunting...

8/11/2016... post week-long silence

So... 9 DAYs later

little more dialog is not acceptable (?)
I'll go to my monolog:

If you don't know how to run a Volt-Ohm Meter
I'm wasting your time (GOOD DIGITAL $10).

Because of the POLARITY REVERSAL (to push the latch up (when radio-released))...
IS A GROND START SEQUENCE..!!

It is not reasonable to look beyond the mechanical contacts (which I ALREADY) noted... previously.

The full open motion
(at the end of the open cycle)...
Should push the contacts (to reverse polarity)... STOPPING THE UPWARD DIRECTION...
The battery contact (close sequence) is a BATTERY START SEQUENCE) is triggered by gentle push of the trunk lid into the LATCH.

It the travels down tightening the trunk-lid into place... and reversing the MOTOR POLARITY again at the FULL CLOSED POSITION

The ONLY thing that can keep the motor running is bad contact in the release switch... or (somebody) HAYWIRED it.

It would HAVE BEEN be nice to know if you UNDERSTAND the electro-mechanical nature of your lock assembly.

HAVE you done any rewiring (HAYWIRING) would be the PRIME CONCERN...

ELSE... It is the trunk latch contacts.

When last I looked ... those parts were still available...

and having spare parts for a collector quality car cannot be that DISTASTFUL...

I'd give it a TRY (I'm just saying)

BBB Industries Premium Alternators Starters Power Steering Products

http://www.rockauto.com/en/catalog/cadillac,1995,deville,4.6l+v8,1025323,electrical-switch+&+relay,trunk+lid+release+switch,4828

1995 CADILLAC DEVILLE 4 6L V8 Trunk Open Warning Switch RockAuto

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