: 1999 Deville , Code says convertor is not locking up



RRG
08-23-04, 05:21 PM
My 1999 275 H P Deville has a code saying that the Torque Convertor is not locking up . The car seems to work fine and the dealer can`t find anything wrong with the transmission . Why does the service engine light keep coming on . :banghead:

Ranger
08-28-04, 12:09 PM
If you want to check to see if the torque converter is locking up try this test. While driving at a steady speed (cruise not engaged) very lightly touch the brake pedal with your left foot. Not enough to engage the brakes but just enough to move the switch at the top of the pedal, just like you would do to disengage the cruise. If the torque converter is engaged, this will disengage it and you should see a slight 200-300 RPM jump.

RRG
08-31-04, 06:13 PM
Thanks Ranger
I did what you said , and it appears my converter is not locking up .As I said before the car works well and my gas milage is good (although I used to drive a S U V ) . So what does that mean and is the fix a major one ???
RRG
P S How can I get that service engine light to stay off ?

Ranger
09-01-04, 04:44 PM
I don't know that much about it but I think the trans has to come out to fix the problem. I would call that major. I think you can just drive it like it is if you want to. It might cost a mile or two per gallon as your RPM will be slightly higher at any given speed above 41 MPH, which is where the converter is supposed to lock up I believe. I am not sure if there is any way to get that SES light off without fixing the problem.

mcowden
09-02-04, 12:38 PM
This might be slightly off-topic, but I'm curious about something... In the Chicago area, emissions testing rules allegedly dictate that the car fails if the SES light is on or if the computer says it's supposed to be on. I don't know if that includes every possible reason for the light or only for emissions-related codes. Anyone know the details of this stuff? If that's true, RRG may not pass an emissions test if he's subject to one where he lives. In that case, he may be stuck with the repair bill or a loss on selling the car.

Geno Castellano
09-02-04, 02:15 PM
It's a bit premature to pull the tranny. When you do the brake switch test you have to be sure and warm the car up thoroughly and drive at highway speeds so as to be sure the torque converter clutch is trying to apply. Hold the gas steady with your right foot and use your left foot to lightly apply the brake pedal just enough to activate the switch. If you let off the accelerator and coast and apply the brakes the test doesn't work as the clutch disengages when coasting anyway. You have to maintain constant load and speed, preferably up a slight grade so as to put some additional load on the trans, to see the effect of the torque converter clutch disengaging when you tap the brakes.

If you are sure the torque converter clutch is not working due to this test then it is just the very first slight step in diagnosing the problem. The torque converter clutch in that trans is called a VCC for Viscous Converter Clutch. It works very similar to the conventional TCC except that there is a viscous coupling in the lockup unit that allows slight creep or slip to make the power delivery smoother when the torque converter is locked.

The system gets 12 volts thru the brake switch to the trans and through the VCC apply solenoid. The ground side of the solenoid goes back out of the tranny and to the PCM. The PCM pulls the circuit to ground to apply the VCC. Missing 12 volts to the circuit, misadjusted brake switch, faulty wiring, failed VCC apply solenoid, failed torque converter, failed PCM, etcetera are all on the list of possible suspects for the torque converter clutch not working and causing the code to set. Impossible to tell without diagnosis and dropping the trans is exactly the last step in diagnosing the problem.

I would find a Cadillac dealer that is familiar with the torque converter clutch diagnosis and have them look at it first. The diagnosis is clearly outlined in a step by step basis in the Cadillac service manual so there is really no excuse for them not knowing how to do it. Use the forum search feature in the tool bar and type in "VCC" or "TCC" or "viscous converter clutch. There's plenty of information there.

RRG
09-02-04, 04:29 PM
Thanks Geno
The service engine light comes on and of . I had an aftermarket market remote starter installed . It works on and off . Could that be effecting the lock up feature of the converter ??
As I said earlier , the car works fine , I just dont like that SES light on ...
RRG

dkozloski
09-03-04, 12:41 PM
The brake switch is quite often used with an auto start to stop the engine if a thief tries to step on the brake to shift into gear. it is very possible that someone has tapped into the wrong wire and got the converter lockup circuit instead of the brake light switch during installation of the device. I would pursue this angle.

Geno Castellano
09-04-04, 12:29 AM
Thanks Geno
The service engine light comes on and of . I had an aftermarket market remote starter installed . It works on and off . Could that be effecting the lock up feature of the converter ??
As I said earlier , the car works fine , I just dont like that SES light on ...
RRG


Yes. Did this problem start when the aftermarket parts were installed? If so, then I think you're on to something.

RRG
09-04-04, 08:19 AM
yes , but averything worked fine for about a year . then the SES light started coming on and of , each time staying on longer . then I began having start problems , you know , the wait three minute deal ...and the remote starter only works occasionly now .The more I read here , the more I think everything is somehow related .
On Sunday I am going on a 7 day road trip , and when I get back I think I will contact the G M rep in this area and ask which dealer here is best qualified to diagnose and fix this problem , and try again .I am just tired of paying 200 dollars to be told they cant find anything wrong and all they do is reset the computer .

RRG
10-12-04, 10:15 AM
I have finally had a diagnosis done that I trust . I am told that the TCC solenoid has failed .
I was also told that it will cost 760.00 (Canadian) to replace it .The transmission has to come out to replace the solenoid . I am getting 25 miles per gallon (30 Canadian) so I am not sure it is worth that much to me . Will leaving it as is hurt the transmission further ?
Thanks
RRG