you need to replace the cluster..
dash display panel needs rebuild
The letter C on an AC display on a 91 Cadillac Deville means cold. It is often the coldest setting available.
uotside temp sensor in front of the radiator has gone bad
I believe fuses are in the trunk!
In the 2000 Cadillac DeVille, the display is located on the dashboard, integrated into the center console. It features a digital readout that provides information such as speed, fuel level, and climate controls. Additionally, it includes a touchscreen interface for the audio and navigation systems, enhancing driver accessibility to various functions.
check fuses
what buttons are used to bring up codes on display of 1994 cadillac etc
there is a button near the spedometer display that switches us and metric
To set the clock on your 1994 Cadillac Seville, turn the ignition key to the "On" position without starting the engine. Press and hold the "HR" button to adjust the hour, and the "MIN" button to adjust the minutes. Release the buttons when the correct time is displayed, and the clock will save the settings. If your model has a digital display, ensure that the display is activated while making adjustments.
The wiring is wrong. Same thing happened to me and I replaced a relay cluster and fixed the wiring it's most likely the yellow wire or memory.
Hold the OFF and WARM buttons on the E.C.C. When 7.0. is displayed on the F.D.C press the HI button once, You should now see E.9.5 displayed on the F.D.C. Then hold the ECON and WARM buttons on the E.C.C. and the F.D.C should now display E.5.0 indicating your in override diagnostic mode and depending on what you want to do use the HI or LO buttons the scroll up or down.
theese are lit by a 16 volt output from the body control module we often find its a bad bcm.