rockfangd

I will find out which wires they are at the base of the column. Pretty sure it goes to the large plug. I do not believe the wires go to the radio. Likely to the IPC. I will post them as soon as I find them. There may be a common ground to all of them that you can cut. 

https://www.ebay.com/itm/354792143186?hash=item529b427952:g:ckwAAOSwRA1kZUqn&amdata=enc%3AAQAIAAAA8G2gVe5T6m8wnZCBDM8Ihgv%2F77GHgdmK9k7c7J2YLz9rNlew6qKyT0D4gugtR6y7SnQyCCKy52qo6yCHgHemqGFZpDstMAFAQr3uXBz%2BDXGcV34LrDl8HKUeSzutESlKBEARqplpcnUKRnkkhlwdaU%2BvMGZUn7JVhVWZGVx0yaU027Iy6z8zAg7ZVC%2Fjer%2BJV41sGizJSxNgmQkbUQ0eEE3%2FuONrmC4PpYgydqTj0iZhzQHRd16I3p3oTIoBt8nJ4V%2B1AVAoQ6xwA%2F28HEygnk97lbmXMDe3tZNyEm1rJ9dOkpLmp27D5qbF8jo6iwVw7g%3D%3D|tkp%3ABFBMmNSr785i
 
 
 
 
Also.....Just FYI.....Lots of BMWs just have press on tips. Very tight but are a press fit. You might be able to see some youtubes on it. You might have some luck there.
 

It's not so much the transmission that needs to be in park......it's the big PNP switch that has to be in 'park'. 
Anyway....at the theft relay....Pin B should have 12v + all the time. If not....blown fuse or fuseable link. 
                                                Pin F should have 12v + during cranking. If not....blown fuse or fuseable link....or PNP switch bad or out out  'park' or 'neutral' position.....or bad ignition switch. 
 
If both of those test OK.....No ground signal is coming from the cluster.....likely a PASS key problem. 

I have an adapter that works through the antenna rather than having to use a cassette. It works a little better than the cassette adapter and is not bad to hook up. Is this something you might be interested in? I bought 2 for my Caddys but am very picky so I do not use them. I just do without.
I have had several GMs of that era and never had a problem. They do not work as well to me with my 97s though. Yours still has the standalone radio unit iirc which they work best on. 
Look up iSimple Radio Mod.    Works with MP3, I Pod, 3.5mm aux. Just not bluetooth. I believe I have the antenna adapters as well because GM ran the smaller antenna ends in that era

I completely agree on the delco tstat. The quality of so many things has been so bad that words cannot describe, and what's worse is nobody seems to care. I have been trying to find and use old stock whenever I can

I don't know if this helps or not but here's a link to Strut Masters:  1997 Cadillac Deville Air Suspension Conversion Kits | Struts | Suspen – Strutmasters

Welcome Back.
I suggest replacing the coolant temp sensor. I say this in reading the original thread and replies that followed. Hot and cold swings over time, bumps and bangs, etc... can have an effect on a sensors ability to be accurate. Ie resistance value slightly off. Do not go with aftermarket if at all possible. I have not had good luck with them being accurate

Couple of pics added.....
Gauge...not sure how accurate the description is....but likely pretty close. Gauge should stay at 12 o'clock. 
Front air baffles. Often damaged in front wrecks. Large lower panel and 2 side air baffles are needed or you can have overheating problems. # 4, 5, 6 and 15. 
Fans. Both should turn freely turned off....may be jammed or broken or missing. A real good scan tool can turn on/off the fans for testing (GM Tech2). This also verifies wiring, relays and fuses. 
Could have possible wire harness damage, blown fuses or blown fuse links. 
The Northstar is also known for pulled head bolts that causes overheating. But....being the car appears to have past front end damage....I would check all that before chasing head bolt issues. 
 

Truly is a crazy market. I have not seen anything quite like this. 
That sounds like some good taste though. Just driving that would make others want it

Well I could not find the clips anywhere. I ended up reusing the original one. Were ok as I carefully removed them.
Got car put away night before salt and brine went down on the roads. Hope it looks as good when I pull it out in the spring.
 
 
 

I never did post my replacement for my bike... 
Been riding this one since September. I actually bought it in August even though I could not ride it then. I have ridden it every time I possibly can. Gets twice the mileage as the cars too lol.
2005 Yamaha VStar 1100. 18k when I bought it. Just over 20k now. Cleans up like a pearl. Well taken care of.
1st pic is when it came home. Rest are my setup as of today. Even got a shot of the Seville. 
May we all be thankful and enjoy our Memorial Day Weekend
 

It does go thru the BCM. The BCMs can and do go bad. They'll do crazy stuff like turn on the hazards 30 minutes after the car is turned off. They do have to be programmed. 
 
From the GM service manual....2008 SRX. 
"Ground is applied at all times at G200 to the turn signal/multifunction switch. The turn signal lamps may only be activated with the ignition switch in the ON or START position. When the turn signal/multifunction switch is placed in either the TURN RIGHT or TURN LEFT position, ground is applied to the body control module (BCM) through either the right turn or left turn signal switch signal circuit. The BCM then applies a pulsating voltage to the front and rear turn signal lamps through there respective voltage supply circuits. Ground for the left and right front turn signal lamp is supplied at G104. Ground for the rear turn signal lamps is supplied at G402 for the left and G401 for the right."
 
Can also be a bad IPC. 
"Turn Signal Indicators Malfunction
Ignition ON, with a scan tool perform the Display Test for the instrument panel cluster (IPC) and observe the turn signal lamp indicators.
⇒ If the turn signal lamp indicators illuminate during the test, replace the BCM. 
⇒ If the turn signal lamp indicators do not illuminate during the test or remain illuminated at all times, replace the IPC." 
 

OK! So, here's the deal....I am quite ecstatic, because, I checked the engine temp while cruising, level ground, and up a few steep hills, and discovered the engine temp WAS in fact running cool. (Although the heater SEEMED to be OK, in the cold weather). So I installed a new 195 degree thermostat, and WOW! The temp is back up to normal, the exhaust is no longer chokingly rich smelling, the engine runs and idles smoother than ever, and best of all, the OD works properly and my fuel mileage is back to normal. SERIOUSLY. I am totally shocked that such a simple remedy could fix all these issues. And of course, I realize I am REALLY lucky, thanks to your help. I hope anybody else who may experience this problem reads this and is as fortunate. Thanks Rockfangd! And Sonjaab too.....      Bill in VT       PS I still have the '99 Deville as well

Another thing I would check is the brake light switch.
If its failed either brake lights or OD wont work.
Used to be a big issue with GM trucks back then.
Just a thought in case it was mentioned and i missed it.

Couple pics of the new steed! 🤠

Welcome to Caddyinfo.
If yours is like the 90s style I would suggest inspecting the plug that goes to the regulator on the alternator. I have misdiagnosed alternators on these because of that plug. Wire will corrode somewhere near the plug and intermittently lose connection

Expensive system to repair. GM did issue a bulletin on ways to turn off the message. 
Of course......GM says this should only be done after replacing the struts...(ok...wink, wink...) And it does mention 1991 Eldorado about 1/2 way down the article. 
https://www.motor.com/magazine-summary/trouble-shooter-april-2006/
 
And some info on the ALDL showing pin IDs. 
https://en.wikipedia.org/wiki/ALDL

You do not need a cable or a scantool. Just a way to ground the proper pin. Bruce nailed what I was looking for.
The indicator is on the module behind the seat iirc

Grounding the diagnostic enable circuit at pin C of the ALDL connector, or by grounding pin D2 to D16 fo the control module connector.  After pin C is grounded, the lamp will be on for 7.5 seconds before beginning the blink code diagnostic sequence.  This is followed by displaying code 12, three times to mark the beginning of the sequence.  Then each stored error code is blinked out, in ascending order.  Each code is displayed three times before proceeding to the next code.  When all codes have been read, the entire code sequence will repeat, starting by blinking code 12 three times.  The sequence will repeat until the diagnostic enable circuit is disconnected.
Codes are read by counting the number of flashes of the LED on the CCR control module.  A code 12 would be indicated by the lamp flashing once, followed by a one second pause, followed by two flashes with a half second pause between flashes.  there is a three second pause between codes.
If the diagnostic mode is entered, and no codes are stored in memory, the control module will continually display code 12.
Error codes
12 Initiation code
23 Left front actuator
24 Right front actuator
25 Left rear actuator
26 right rear actuator
31 lift/dive input error
32 Lateral acceleration switch error
 

Well I have some good news.
I went on a hunch and ordered a fuel pump/sending unit. (MY replacement unit still has warranty)
I drove the car until gas was as low in the tank as I was comfortable with, I pulled the tank tonight.
The problem was the sending unit. I have been pulling my hair out since this issue started, well over a year ago. lower the tank got the crazier the gauge got. I went crazy driving it the last 2 days.
The design is absolutely terrible, I regret replacing the unit with an aftermarket unit. The saving was not worth it. One of the 2 (Feelers) was broken and in the bottom of the tank. I am glad I did not take apart the back seat, or harness. I had a gut feeling.
It was very peaceful driving home tonight. Had 2 gallons upon assembly, added 10 gallons. IS accurate.
Old unit was 5 years old, and had about 12k miles on it. If it happens again  I am bypassing it.
Note To anyone who cares. DO NOT BUY AFTERMARKET. The oem ones are not the best solution, but they are the only one that appear to last.
I also left the car running when I got home while I checked my mail. Normally If I left the car running for more than about 30 seconds it would pop the check engine light saying lean both banks. Hopeful the pump may have resolved this issue too 
Pic shows what it is supposed to look like. Note the 2 brass colored feelers. They are cheesy, and the black arm is sloppy (Brand new)

Welcome to CaddyInfo.
A few suggestions here.
I recommend jacking up the front end. Turn the wheel to the left, then to the right. Feel for binding. This is a long shot but you may have a sticky balljoint. If they are greasable I recommend greasing them well.
There was an issue with the gearboxes occasionally but it has been a long time since I ran into one with the issue.

Welcome to CaddyInfo.
I went through this on my 1997 Seville. I have the same system. I tried for awhile to get the proper parts but they are long discontinued iirc. At least I had no luck. I went with the system that does not function like the originals (bypasses) If I had a choice I would not have. I do notice a difference in handling compared to the original setup. To give you an idea mine has been bypassed for probably 8 years now. I run Arnotts in the rear and have Monroe struts in the front. My original struts had leaked and were making noise.
I assume you have RPO FE1 Soft ride
22400527 Left front
22400528 Right front
Did the dealer tell you they can get the oem parts?
I believe Compatibility for the 1996 was 1995-1996 only.
My 1997 was 1997 only. Not sure what the difference is. I know the early ones had the plug on top of the strut but all of the E/K I have dealt with in the last 10 years or so have the sensor down by the base of the strut

Thanks. Fuel is a sore subject... 
a few unique problems to these Caddys is the lack of manufacturers of parts. For my Seville parts are nearly impossible to find, and have been for a long time now. 
They are not like Chevys, Fords, and Chryslers that you could get most parts for.
 

Clear the light and see how long it takes to come back. 
See if it shudders around 41 mph. If it shudders and the light triggers then it is very likely the torque convertor that failed.
Typically that code alone means torque convertor.
If it shudders but does not trigger the light it may be in early stages. These were hard to tell when something is not right. They seem to ride nice no matter what lol.
If it does not shudder at all around 41 mph and lockup is smooth then I would just monitor it to see if it comes back. 

Been put off by local sloppy wheel balances for years......they simply are not doing it right....
Firestone....Discount Tire....
"We'll put our best new guy on it.".....yikes..
It cannot be done correctly in one or two 90 second spins. You really need about 20-30 minutes per wheel to get them right.
Firestone finally pissed me off. Needed one BMW TPMS sensor installed on a single wheel....had the wheel off the car....had the new OEM sensor in hand....."Sorry....We only put our TPMS sensors in." 
 
Sooo......purchased a wheel balancer. So far....2 cars now driving perfect at highway speeds....A BMW and a Chevrolet.
 
https://www.derekweaver.com/rodders-garage/wheel-balancers/weaver-w-937-40-wheel-balancer/ny 
 
Any questions let us know. Excellent product.