You might (probably not) find it in the factory service manuals.
Index of /FSM/Titan/2008_Titan
I do not find them very helpful---especially with electrical issues. I looked at several chapters and found nothing regarding the wires in hte steering column.
The chapter names are encrypted for some reason.
I translated the chapter names for the 2015 Titan (which I have). Yours may be similar:
ACCELERATOR CONTROL SYSTEM = acc.pdf
AUDIO, VISUAL & NAVIGATION SYSTEM = av.pdf
AUTOMATIC DRIVE POSITIONER = adp.pdf
BODY CONTROL SYSTEM = bcs.pdf
BODY REPAIR = brm.pdf
BRAKE CONTROL SYSTEM = brc.pdf
BRAKE SYSTEM = br.pdf
CHARGING SYSTEM = chg.pdf
CRUISE CONTROL SYSTEM = ccs.pdf
DEFOGGER = def.pdf
DOOR LOCK AND KEY = dlk.pdf
DRIVELINE = dln.pdf
ENGINE CONTROL SYSTEM = ec.pdf
ENGINE COOLING SYSTEM = co.pdf
ENGINE LUBRICATION SYSTEM = lu.pdf
ENGINE MECHANICAL = em.pdf
EXHAUST SYSTEM = ex.pdf
EXTERIOR = ext.pdf
EXTERIOR LIGHTING SYSTEM = exl.pdf
FRONT AXLE = fax.pdf
FRONT SUSPENSION = fsu.pdf
FUEL SYSTEM = fl.pdf
GENERAL INFORMATION = gi.pdf
GLASS & WINDOW SYSTEM = gw.pdf
HEATER & AIR CONDITIONING CONTROL SYSTEM = hac.pdf
HEATER & AIR CONDITIONING SYSTEM = ha.pdf
HORN = hrn.pdf
INSTRUMENT PANEL = ip.pdf
INTERIOR = int.pdf
INTERIOR LIGHTING SYSTEM = inl.pdf
LAN SYSTEM = lan.pdf
MAINTENANCE = ma.pdf
METER, WARNING LAMP & INDICATOR = mwi.pdf
MIRRORS = mir.pdf
PARKING BRAKE SYSTEM = pb.pdf
POWER CONTROL SYSTEM = pcs.pdf
POWER OUTLET = pwo.pdf
POWER SUPPLY, GROUND & CIRCUIT ELEMENTS = pg.pdf
POWER WINDOW CONTROL SYSTEM = pwc.pdf
REAR AXLE = rax.pdf
REAR SUSPENSION = rsu.pdf
ROAD WHEELS & TIRES = wt.pdf
ROOF = rf.pdf
SEAT = se.pdf
SEAT BELT = sb.pdf
SECURITY CONTROL SYSTEM = sec.pdf
SRS AIRBAG = sr.pdf
SRS AIRBAG CONTROL SYSTEM = src.pdf
STARTING SYSTEM = str.pdf
STEERING SYSTEM = st.pdf
TRANSAXLE & TRANSMISSION = tm.pdf
VENTILATION SYSTEM = vtl.pdf
WARNING CHIME SYSTEM = wcs.pdf
WIPER & WASHER = ww.pdf