You might want access to a factory service manual and body diagnostic procedures manual if you are to diagnose this yourself. Powers and grounds must be present at the BCM (body control module).
Then see if it can communicate with a scan tool such as the DRB3 or equivalent. All the symptoms that you list are BCM related. It can store fault codes and might be partially functional.
The body control module (BCM) supplies vehicle
occupants with visual and audible information and
controls various vehicle functions. To provide and
receive information, the module is interfaced to the
vehicle’s serial bus communication network (Programmable
Communication Interface or PCI bus).
This network consists of the powertrain control
module (PCM), the memory/heated seat module
(MHSM, MSM or HSM), the sentry key immobilizer
module (SKIM), the transmission control module
(TCM), the electro/mechanical instrument cluster
(MIC), the driver door module (DDM), the passenger
door module (PDM), the airbag control module
(ACM), the antilock brake module (ABS), the optional
electronic vehicle information center (EVIC),
the optional PCI radio and the optional automatic
zone control module (AZC). The BCM is operational
when battery power is supplied to the module,
ignition switch power is needed for ignition
switched functions.
The BCM provides the following new features:
² Full control of all exterior and interior lamps,
including these features:
> A Battery Saver automatically turns off all
exterior and interior lamps within 8 minutes
after the ignition is turned off, if they are not
turned off by the driver. This includes the
front and rear reading/courtesy lamps and the
cargo area dome lamp, even if they are turned
on manually.
> Theater-style interior lighting dims gradually
when the doors are closed.
> Interior courtesy lamp operation may be ‘‘defeated’’
using the dimmer control ring on the
left stalk switch.
> Instrument panel light intensity may be maximized
for daytime visibility with the head
lamps or parking lights by using the dimmer
control ring on the left stalk switch.
² A refined Accessary/Sunroof Delay allows operation
of the sunroof as well as the power windows.
In addition, the time has been extended from 30
to 45 seconds after the ignition is switched off for
added convenience. As in the past, the delay
terminates (window and/or sunroof ceases) if a
door is opened, which helps protect occupants
from possible injury.
² Beep tones for warnings and programming actions
associated with the Sentry Key Immobilizer
system and the EVIC.
The BCM also provides the following features:
² Intermittent wipe and low speed wiper control
² Wiper system status
² Ignition on/off timer
² VF displays synchronization
² Rear door and liftgate ajar status
² Acquisition & transmission of external temperature
² A/C select switch status
² Chime
² Courtesy lamps with fade to off feature
² Reading lights/glove box lamp load shedding control
² Exterior lighting control including automatic
headlamps, fog lamp control and parking lamps
² Exterior lamp status
² Headlamp time delay upon ignition off and headlamps
switch off
² Parade mode
² Illuminated entry
² Instrument panel dimming
² Vehicle theft security system with panic & horn
and hazard lamp activation
² Key-in ignition switch interface
² Brake fluid level switch/park brake switch interface
² Seatbelt reminder
² Speed sensitive intermittent wipe control
² Remote radio switch interface to radio
² Vehicle ignition status
² BCM self diagnostics
² Liftgate courtesy lamp disable
² Rear window defogger control
² Accessory delay control (windows and sunroof)
² Fuel economy and distance to empty (DTE) calculations
² Heated seat switch status
² Exterior lamp load shed
² Support of EVIC programmable features
