Grand Cherokee 2WD V8-4.7L VIN N (2000)
Body Control Module: Component Tests and General Diagnostics
Component Testing
In order to obtain conclusive testing of the Body Control Module (BCM), all of the electronic modules that provide inputs to, or receive outputs from the
BCM must also be checked. The most reliable, efficient, and accurate means to diagnose the BCM requires the use of a DRB scan tool and the proper
Diagnostic Procedures. The DRB scan tool can provide confirmation that the Programmable Communications Interface (PCI) data bus network is
functional, that all of the electronic modules are sending and receiving the proper messages on the PCI data bus, and that the BCM is receiving the
proper hard wired inputs and relaying the proper hard wired outputs to perform its many functions.
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.
