Cadillac Repair: 1992 DeVille, climate control, letters and numbers

Question
Can I Jump the a and b terminals to read error codes?

Answer
NO1. Ignition ON. Engine OFF.

2. Simultaneously push and hold the OFF and WARMER buttons on the climate control panel for 3 seconds and release the buttons.

3. diagnostic codes will appear and then stop.

4. tell me exactly how the letters and numbers display as these are your codes.

5. turn ignition OFF.