Dodge Ram 2004 Service Manual page 119

NO PCI LOOPBACK —
TEST
7 NOTE: Ensure there is PCI bus communication with other modules. If not,
refer to the PCI Bus Communication Failure symptom and repair as
necessary.
WARNING: TO AVOID PERSONAL INJURY OR DEATH, TURN THE IGNI-
TION OFF, DISCONNECT THE BATTERY AND WAIT TWO MINUTES BE-
FORE PROCEEDING.
Disconnect the ACM harness connector.
Connect the appropriate Load Tool ACM Adapter to the ACM connector.
Turn the ignition on and then reconnect the Battery.
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. Press F2 again
when complete.
Connect the Black lead to the chassis ground. Connect the Red lead to the PCI Bus
circuit in the ACM connector.
Observe the voltage display on the DRB Lab Scope.
Does the voltage pulse from 0 to approximately 7.5 volts?
Yes → Go To 8
→ Repair the PCI Bus circuit for an open.
No
8 WARNING: TO AVOID PERSONAL INJURY OR DEATH, DISCONNECT THE
BATTERY AND WAIT TWO MINUTES BEFORE PROCEEDING.
WARNING: IF THE AIRBAG CONTROL MODULE IS DROPPED AT ANY
TIME, IT MUST BE REPLACED. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN ACCIDENTAL AIRBAG DEPLOYMENT
AND PERSONAL INJURY OR DEATH.
If there are no possible causes remaining, view repair.
Repair
9 Turn the ignition off.
Disconnect the PCM/ECM harness connector. Note: If equipped with NGC follow the
caution below.
CAUTION: DO NOT PROBE THE PCM HARNESS CONNECTORS. PROBING
THE PCM HARNESS CONNECTORS WILL DAMAGE THE PCM TERMI-
NALS RESULTING IN POOR TERMINAL TO PIN CONNECTION. INSTALL
MILLER SPECIAL TOOL #8815 TO PERFORM DIAGNOSIS.
Disconnect the DRB from the Data Link Connector (DLC).
Disconnect the negative battery cable.
Measure the resistance of the PCI Bus circuit between the Data Link Connector
(DLC) and the PCM/ECM harness connector.
Is the resistance below 5.0 ohms?
Yes → Go To 10
→ Repair the PCI Bus circuit for an open.
No
Continued
ACTION
Perform __AIRBAG VERIFICATION TEST - VER 1.
Replace the Airbag Control Module in accordance with Service
Instructions.
Perform __AIRBAG VERIFICATION TEST - VER 1.
Perform __AIRBAG VERIFICATION TEST - VER 1.
105
AIRBAG
APPLICABILITY
All
All
All