Problem Description and Possible Solution
The torque converter clutch (TTC) may stop working due to an internal transmission failure. The Check Engine Light will illuminate if this occurs. Our technicians tell us the transmission will require dis-assembly to correct this concern.
Average mileage: 104,477 (16,300–225,000)
10 people reported this problem
SES light went on, and my mechanic advised that it was the torque converter, or the switch inside the transmission. The car seemed to run fine.
Changed the transmission fluid, reset the SES, and drove for about 18 months without the SES light.
I have reset the SES light many times over the last three years, car now has 80,000 miles, and still runs great.
SES light now either stays on, or will come back in two or three days after resetting.
After purchasing this vehicle I was driving back home and I realized that the Service engine soon light was on. I had it checked and it turns out that the Transmission clutch is not working properly because the Transmission Solenoid is not functioning. This is a common problem with All Cadillacs with the NorthStar Engine. It cost about $2500 to repair the problem but, at that price you can buy a remanufactured Transmission from GM or Cadillac with a 3 year warranty, and don't forget to add an additional $1200 for parts and labor. I estimate you will end up Spending $3500 - $4000 on repairing this problem.