Liberty Sport 4WD L4-2.4L VIN 1 (2002)
Body Control Module: Component Tests and General Diagnostics
Component Testing
The hard wired inputs to and outputs from the Body Control Module (BCM), as well as other hard wired circuits for this module may be diagnosed and
tested using conventional diagnostic tools and procedures. However, conventional diagnostic methods may not prove conclusive in the diagnosis of the
BCM, the Programmable Communications Interface (PCI) data bus network, or the electronic messages received and transmitted by the BCM over the
PCI data bus. The most reliable, efficient, and accurate means to diagnose the BCM and the PCI data bus network inputs to and outputs from this module
requires the use of a DRBIII scan tool. Refer to the appropriate diagnostic information.
Refer to the appropriate wiring information. The wiring information includes wiring diagrams, proper wire and connector repair procedures, further
details on wire harness routing and retention, as well as pin-out and location views for the various wire harness connectors, splices and grounds.
WARNING: ON VEHICLES EQUIPPED WITH AIR-BAGS, DISABLE THE SUPPLEMENTAL RESTRAINT SYSTEM BEFORE
ATTEMPTING ANY STEERING WHEEL, STEERING COLUMN, DRIVER AIRBAG, PASSENGER AIRBAG, SEAT BELT TENSIONER,
FRONT IMPACT SENSORS, SIDE CURTAIN AIRBAG, OR INSTRUMENT PANEL COMPONENT DIAGNOSIS OR SERVICE.
DISCONNECT AND ISOLATE THE BATTERY NEGATIVE (GROUND) CABLE, THEN WAIT TWO MINUTES FOR THE SYSTEM
CAPACITOR TO DISCHARGE BEFORE PERFORMING FURTHER DIAGNOSIS OR SERVICE. THIS IS THE ONLY SURE WAY TO
DISABLE THE SUPPLEMENTAL RESTRAINT SYSTEM. FAILURE TO TAKE THE PROPER PRECAUTIONS COULD RESULT IN
ACCIDENTAL AIRBAG DEPLOYMENT AND POSSIBLE PERSONAL INJURY.
Road Testing A Complaint Vehicle
ROAD TEST WARNINGS
Some complaints will require a test drive as part of the repair verification procedure. The purpose of the test drive is to try to duplicate the diagnostic
code or symptom condition.
CAUTION: Before road testing a vehicle, be sure that all components are reassembled. During the test drive, do not try to read the DRB III screen
while in motion. Do not hang the DRB III from the rear view mirror or operate it yourself. Have an assistant available to operate the DRB III.
Six Step Troubleshooting Procedure
SIX-STEP TROUBLESHOOTING PROCEDURE
Diagnosis is done in six basic steps:
1. Verification of complaint
2. Verification of any related symptoms
3. Symptom analysis
4. Problem isolation
5. Repair of isolated problem
6. Verification of proper operation
Vehicle Preparation For Testing
VEHICLE PREPARATION FOR TESTING
Make sure the vehicle being tested has a fully charged battery. If it does not, false diagnostic codes or error messages may occur.
