One problem related to alternator/generator/regulator has been reported for the 2003 Cadillac CTS. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2003 Cadillac CTS based on all problems reported for the 2003 CTS.
2003 Cts - service tracking system began to display and engage frequently. Took to local dealer and was told nothing was wrong with vehicle. Problem continued and began vibrating badly and pulling toward left (unable to brake). Returned vehicle several times before they replaced "steering sensor" $650. 00. Two months later began to lose power immediately after start up, dealer replaced battery. While driving vehicle home problem began again. Displayed low battery, then multiple warning lights for service (abs, tracking, airbag ect. . . ). Returned vehicle to dealer and they are currently replacing alternator. I have no confidence that this is the real problem based on what I have read on-line regarding this same issue. I also have same leakage issues from both coolant and oil sources that I have read on-line. Dealer continues to tell me to replace both gaskets and thermostat. These again are common issues that are posted consistently on-line by consumers. These are seriously dangerous failures based on people's personal safety. Gm must step up and honor these safety issues by recalling these items. Inability to control vehicle due to tracking system engaging and not able to brake, vehicle losing power and stalling while driving 50 miles an hour, and lastly fire hazard due to leaking plastic valve cover gaskets.