Dodge Ram 2004 Service Manual page 309

*NO RESPONSE FROM TRANSFER CASE CONTROL MODULE —
Continued
TEST
4 Note: Ensure there is PCI Bus communication with other modules on the
vehicle before proceeding. If not, refer to the symptom list from the menu
and repair as necessary.
Turn the ignition off to the lock position.
Disconnect the TCCM harness connector.
Use Scope input cable CH7058, Cable to Probe adapter CH7062, and the red and
black test probes.
Connect the scope input cable to the channel one connector on the DRB. Attach the
red and black leads and the cable to probe adapter to the scope input cable.
With the DRBIII select Pep Module Tools.
Select lab scope.
Select Live Data.
Select 12 volt square wave.
Press F2 for Scope.
Press F2 and use the down arrow to set voltage range to 20 volts. Set Probe to x10.
Press F2 again when complete.
Connect the Black lead to the chassis ground. Connect the Red lead to the PCI Bus
circuit in the TCCM connector.
Turn the ignition on.
Observe the voltage display on the DRBIII Lab Scope.
Does the voltage pulse from 0 to approximately 7.5 volts?
Yes → Go To 5
→ Repair the PCI Bus circuit for an open.
No
5 If there are no possible causes remaining, view repair.
Repair
ACTION
Perform TRANSFER CASE VERIFICATION TEST.
Replace the Transfer Case Control Module in accordance with the
service information.
Perform TRANSFER CASE VERIFICATION TEST.
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COMMUNICATION
APPLICABILITY
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