RAM 2500 Truck 2WD L6-5.9L DSL Turbo VIN C (2002)
Body Control Module: Symptom Related Diagnostic Procedures
The hard wired inputs to and outputs from the Central Timer Module (CTM) may be diagnosed and tested using conventional diagnostic tools and
methods. 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.
However, conventional diagnostic methods may not prove conclusive in the diagnosis of the high-line/premium CTM. In order to obtain conclusive
testing of the high-line/premium CTM, the Chrysler Collision
Detection (CCD) data bus network and all of the electronic modules that provide inputs to or receive outputs from the CTM must also be checked. The
most reliable, efficient, and accurate means to diagnose the high-line/premium CTM, the CCD data bus network, and the electronic modules that provide
inputs to or receive outputs from the high-line/premium CTM requires the use of a DRBIII scan tool and the appropriate diagnostic information. The
DRBIII scan tool can provide confirmation that the CCD data bus network is functional, that all of the electronic modules are sending and receiving the
proper messages over the CCD data bus, and that the CTM is receiving the proper hard wired inputs and responding with the proper hard wired outputs
needed to perform its many functions.
WARNING: ON VEHICLES EQUIPPED WITH AIRBAGS, DISABLE THE AIRBAG SYSTEM BEFORE ATTEMPTING ANY STEERING
WHEEL, STEERING COLUMN, OR INSTRUMENT PANEL COMPONENT DIAGNOSIS OR SERVICE. DISCONNECT AND
ISOLATE THE BATTERY NEGATIVE (GROUND) CABLE, THEN WAIT TWO MINUTES FOR THE AIRBAG SYSTEM
CAPACITOR TO DISCHARGE BEFORE PERFORMING FURTHER DIAGNOSIS OR SERVICE. THIS IS THE ONLY SURE
WAY TO DISABLE THE AIRBAG SYSTEM. FAILURE TO TAKE THE PROPER PRECAUTIONS COULD RESULT IN
ACCIDENTAL AIRBAG DEPLOYMENT AND POSSIBLE PERSONAL INJURY.
NOTE: The following tests may not prove conclusive in the diagnosis of the high-line or premium versions of the Central Timer Module (CTM). The
most reliable, efficient, and accurate means to diagnose the high-line or premium CTM requires the use of a DRBIII scan tool and the
appropriate diagnostic information.
1. Check the fused B(+) fuse (Fuse 13 - 10 ampere) in the Junction Block (JB).
If OK, go to Step 2.
If not OK, repair the shorted circuit or component as required and replace the faulty fuse.
2. Check for battery voltage at the fused B(+) fuse (Fuse 13 - 10 ampere) in the JB.
If OK, go to Step 3.
If not OK, repair the open fused B(+) circuit between the JB and the Power Distribution Center (PDC) as required.
3. For a base version CTM, check the fused ignition switch output (st-run) fuse (Fuse 11 - 10 ampere) in the JB. For a high-line/premium version
CTM, check the fused ignition switch output (run-acc) fuse (Fuse 6 - 25 ampere) in the JB.
If OK, go to Step 4.
If not OK, repair the shorted circuit or component as required and replace the faulty fuse.
4. Turn the ignition switch to the ON position. For a base version CTM, check for battery voltage at the fused ignition switch output (st-run) fuse
(Fuse 11 - 10 ampere) in the JB. For a high-line/premium version CTM, check for battery voltage at the fused ignition switch output (run-acc)
fuse (Fuse 6 - 25 ampere) in the JB.
If OK, go to Step 5.
If not OK, repair the shorted circuit or component as required and replace the faulty fuse.
5. Turn the ignition switch to the OFF position. Disconnect and isolate the battery negative cable. Remove the CTM from its mounting bracket to
access the CTM wire harness connector(s). Disconnect the instrument panel wire harness connector(s) for the CTM from the CTM connector
receptacle(s). Check the wire harness connectors and the CTM receptacles for loose, corroded, or damaged terminals and pins.
If OK, go to Step 6.
If not OK, repair as required.
6. Check for continuity between the ground circuit cavity of the instrument panel wire harness connector (Connector C1) for the CTM and a good
ground. For the high-line/premium version of the CTM only, repeat the check between the ground circuit cavity of the instrument panel wire
harness connector (Connector C2) for the CTM and a good ground. In each case, there should be continuity.
If OK, go to Step 7.
If not OK, repair the open ground circuit(s) to ground as required.
7. Reconnect the battery negative cable. Check for battery voltage at the fused B(+) circuit cavity of the instrument panel wire harness connector
(Connector C1) for the CTM.
If OK, go to Step 8.
If not OK, repair the open fused B(+) circuit between the CTM and the JB as required.
8. Turn the ignition switch to the ON position. Check for battery voltage at the fused ignition switch output (st-run) circuit cavity (base version) or
fused ignition switch output (run-acc) circuit cavity (high- line/premium version) of the instrument panel wire harness connector (Connector C1)
for the CTM.
