If you do try to remove the side cover, take notice of where the studded bolts are in the cover. They will need to go back in the same location. By "studded", I mean the bolts that have extended, threaded ends on them for brackets.
The solenoids are held to the valve body with clips, so no need to unbolt anything else(once the side cover is off).
Also, don't be surprised if the connector clips break when you disconnect them from the solenoids. They get brittle with age/heat cycles, and break easily. The connector will still function properly, tho.
The TFT sensor is plastic, and very easy to break. It is normally only finger tight in the valve body, so don't try to tighten it down with a wrench.
hth

 

Thanks for advice

I had chang the PCS, but problem still..
I didn't drive yet with car, too much snow outside.
But when I put transmission at D or R, very hard shift again!
I put scanner, and problem is always here : 76 force motor malfunction
I'm sad!

New PCS :



Ho-hisse !



The side cover :



More photos:
http://cadillac-sts.skyrock.com/8.html

 

Have you cleared the codes yet? If the code(s) is still in the PCM, it will still have issues. If the codes were cleared, and the problem is still there, that leaves either a problem in the harness/connectors, or the PCM. I have seen harness connectors with massive corrosion behind the little rubber "seal" that is down inside of the connector. You may want to pull that seal out, and have a look at the area behind it...

 

Oh, thanks for your quikly answer.

Yes I had cleared the code

 

Work of today :

- First I have disconnect again the 20way-connector, and check behind (inside the connector ==> OK
- Then check (with ohmmeter) the purple and blue wire (side of transmission) and found 6 ohms (must be resistance between 3 and 8 ohms) ==> OK
- Then check harness between 20/connector and the white connector of PCM ==> OK
- Then connect again the 20way-connector and put ohmeter between trans pressure control solenoid high and low terminals (white connector)of PCM harness (C15 & C16) and found 6 ohms ==> OK
Then put ohmmeter between terminal C15 & C16 and ground , nothing ==> OK

The result : I order one new PCM . . .

 

Today,I have put the new PCM at car.

First the good news:

76 force motor malfunction is disappear !

Second, the bad news :

94 shift ratio A problem is back !

+ 80 throttle position sensor - idle not learned after PROM reset

I have drive car a little before, transmission go on safety system at first gear.
I get mad with all these problem !

What can I do now ?

Ah, and bord computer (when I start car) say me that I must chang the transmission oil ? But it's new !

 

Today, I checked both shift solenoid A & B . To do this, I have disconnected the connector of PCM harness and put E4 and E5 at ground, put key on, and listened under car, near valve body : both valve are OK, because I had listened it !
It mean :
- No problem of valve (They are new anyway)
- No problem of harness , from valve to PCM
- New PCM

What else ?

Internal leak of valve body ?

 

The new PCM will need to have the idle relearned. The service manual should have that procedure, if you have the manual. If not, I can e-mail the relearn procedure to you.

The shift ratio A code does not necessarily mean there is a shift solenoid problem. It only means that a shift was commanded, and the PCM did not see a change of ratio. This could be due to a faulty speed sensor/wiring, or even the wrong gear ratio of the transmission.
Do you know if the transmission has ever been out of the car, or possibly changed at some time?
Does the car not shift at all, it just stays in 1st gear?
A stuck shift valve could cause that, also, but the symptoms you are describing sound more like an incorrect ratio trans, or a faulty speed sensor signal to the PCM.

 

Well,
On order : (about code 94)
When I had buy car I had all speed at transmission.
After some thousands miles, suddenly, at freeway, the 4 speed disappear and the transmission went at 1.
Now the problem is like this (with all new parts)
- After clear code, and When I put transmission at 3 and drive car, evrything OK and no code 94 appear The car go at 1 to 2 and 2 to 3 without any kind of harsh shift.
But when I want put transmission at 4 and drive it, the car (when transmission go from 3 to 4) go suddenly at 1 and the code 94 appear.
The car was good at start, the this problem suddenly happen. It mean that something (who was good before) is broken or stuck or something else. But My question now is: What ? Because to chang parts on car, it's not problem,I must only now what I can chang ? when ,(and if) I have speed sensor problem, the PCM will appear one code about this, no ?
About code 80
Yes I'm interested about the procedure : memez@mrachassis.com

 

Outside Air temp more than 50*F(10*C), so the A/C compressor will engage.
Start engine and allow to idle until coolant temp is 176*F(80*C).
Idle for an additional 5 minutes.
With engine running, enter On Board diagnostics.
Turn engine Off. Wait 20 seconds, then turn ign. ON, with engine Off. Re-enter OB diagnostics, turn key Off, wait 20 seconds(again),turn ign ON.
Turn ign. Off. Wait 20 seconds, then start engine. Apply brakes, and place trans into Drive. Turn Climate Control to Off and allow engine to idle for one minute.
Turn Climate Control to "Auto" position and make sure the A/C compressor engages. Allow engine to idle for one minute. Place trans into Park, and turn ign. Off.

btw...this procedure will NOT work if the A/C will not come on, so if your A/C doesn't work for some reason, the idle relearn will not happen.
On the 94 code, if all of the electrical stuff is good, and it appears that you have tested everything correctly, you have two possible problems.
Either the transmission is slipping in, or has no 4th gear, or you have the wrong ratio trans in the car.
When the trans shifts into 4th gear, does it "neutralize", like it's in neutral, or does it feel like it shifts, but slips?
The strategy for the TCM gets very specific in 4th gear, and it will not allow for any speed differences other than what it expects to see. This is why a speed sensor, an incorrect ratio, or slipping band(or clutches) can set this code.
I had a 93-94 model STS in the shop that had the exact same issue. Worked fine 1-2-3, but as soon as 4th gear was commanded, it set a ratio code, and shifted HARD. I fought with this thing for a week before I realized it may have the wrong ratio in it. As I found out, by checking the VIN on the trans, it had been swapped. I fixed this one by simply changing the differential("final drive") gears, which can be done with the trans in the car. Worked like a champ after that.
If your trans is NOT burnt up, I have to believe it is the incorrect ratio.

update:
I went back and re-read all of the posts. You say that originally, the transmission was working fine, and then the problems started after a few thousand miles. This tells me that the ratio is probably correct...which is good. The bad news is, the trans has probably burnt the band for overdrive.
The two shift solenoids are good, since it has 1st gear, so you can rule out a solenoid problem. There is a VERY small chance that a shift valve is stuck, but I've built probably 50+ 4T80Es, and I've maybe seen ONE that had stuck valves. More than likely, if one valve is stuck, there are others that will also be stuck, which would create more problems than you are having.