2003 Lincoln Town Car, krystal PN 13-976 circuit board

I'm having issues with the crystal coach circuit board I see it seems to have A digital to analog conversion system in it along with the standard 18 or 20 relays while running the air conditioner stays on full blast and there is no control of rear locks or air conditioning fan speed temperature accessory in the rear so I'm thinking the digital might be gone in it anyways im trying to troubleshoot this issue I'm an electronics technician and I'm trying to fix this for my friend does anyone have a schematic or even an operation user's manual