Confused

Hey Everyone. im here doing some research for my father in law. he has a 1995 cadillac seville. Problem: when it runs cold it runs good. but when the engine starts heating up the tranny seems to slip. changed the speed sensor, seemed to help but it again starting slipping. under the impression that it is NOT a tranny issue, read some of your forums on other caddy issues and read something about a broken solenoid, could this cause the tranny to slip. any suggestions?

Check for trouble codes as follows:

To enter diagnostic mode:
1. Turn ignition "ON."
2. Depress the "OFF" and "WARMER" buttons on the Climate Control Center (CCC) simultaneously and hold until the segment check appears on the Instrument Panel Cluster (IPC).

Use the link below to find out what the codes mean:

http://myweb.accessus.net/~090/dtcobd1.html