Symptom:
*NO RESPONSE FROM PCM (PCI BUS) - JTEC
POSSIBLE CAUSES
PCM PCI NO RESPONSE
PCI BUS CIRCUIT OPEN
POWERTRAIN CONTROL MODULE
TEST ACTION APPLICABILITY
1 Turn the ignition on.
NOTE: As soon as one or more module communicates with the DRB, answer
the question.
With the DRBIIIt, enter Anti-Lock Brakes.
With the DRBIIIt, enter Body then Electro/Mechanical Cluster (MIC).
With the DRBIIIt, enter Passive Restraints then Airbag.
Were you able to establish communications with any of the modules?
All
Yes → Go To 2
No → Refer to symptom PCI Bus Communication Failure in the Com-
munications category.
Perform POWERTRAIN VERIFICATION TEST VER - 1.
2 With the DRBIIIt read PCM Diagnostic Trouble Codes. This is to ensure power and
grounds to the PCM are operational.
NOTE: If the DRBIIIt will not read PCM DTC’s, follow the NO RESPONSE
TO PCM (SCI only) symptom path.
NOTE: If the vehicle will not start and the DRBIIIt displays a no response
message, refer to the appropriate symptom in the powertrain diagnostic
procedures.
Turn the ignition off.
Disconnect the PCM C3 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 DRBIIIt. Attach
the red and black leads and the cable to probe adapter to the scope input cable.
With the DRBIIIt 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 PCM ground. Connect the Red lead to the PCI Bus
circuit in the PCM connector.
Turn the ignition on.
Observe the voltage display on the DRBIIIt Lab Scope.
Does the voltage pulse from 0 to approximately 7.5 volts?
All
Yes → Replace and program the Powertrain Control Module in accor-
dance with the Service Information.
Perform POWERTRAIN VERIFICATION TEST VER - 1.
No → Repair the PCI Bus circuit for an open.
Perform POWERTRAIN VERIFICATION TEST VER - 1.
282
COMMUNICATION
To Next Page
Loading...
