No Response From Transmission Control Module

Possible Causes:

No Response From Transmission Control Module
Fused Ignition Switch Output (Run/St) Circuit Open
Fused Ignition Switch Output (Start) Circuit Open
Fused B+ Circuit Open
Ground Circuit(s) Open
Powertrain Control Module
PCI Bus Circuit Open
Body Control Module

Testing

Turn ignition off. Connect scan tool to Data Link Connector (DLC). Turn ignition on. Using scan tool, attempt to communicate with Instrument Cluster, then Body Control Module (BCM). If scan tool communicates with either module, go to next step. If scan tool does not communicate with either module, perform PCI BUS COMMUNICATION FAILURE test.

WARNING: Do not probe the PCM harness connectors. Probing the PCM harness connectors will damage the PCM terminals resulting in poor terminal-to-pin connection.

NOTE: Test light must illuminate brightly in steps 2 - 5 . If test light does not illuminate, or illuminates dimly, circuit being tested must be repaired as necessary.

Turn ignition off. Disconnect PCM harness C1 connector. Turn ignition on. Using a 12-volt test light connected to ground, probe terminal No. 11, fused ignition switch output start/run circuit (Dark Blue/White wire). See Figure . If test light illuminates brightly, leave PCM connector disconnected and go to next step. If test light does not illuminate brightly, repair open in Red/White wire.
Remove engine starter motor relay in Power Distribution Center (PDC). See Figure and Figure . Using 12-volt test light connected to ground, probe fused ignition switch output start circuit (Yellow/Black wire). Observe test light while momentarily turning ignition switch to start position. If test light illuminates brightly, leave PCM connector disconnected and go to next step. If test light does not illuminate brightly, repair open in Yellow wire and install engine starter motor relay.
Install engine starter motor relay. Using 12-volt test light connected to ground, probe fused B+ circuit (Red wire). If test light illuminates brightly, leave PCM connector disconnected and go to next step. If test light does not illuminate brightly, repair open in Red wire(s).
Using 12-volt test light connected to battery voltage, probe PCM harness connector, ground circuit No. 9 (Black/Tan wire) and No. 18, ground circuit (Black/Tan wire). If test light illuminates brightly at both circuits, leave PCM connector disconnected and go to next step. If test light does not illuminate brightly at either circuit, repair open in Black/Tan wires.
Using scan tool, attempt to communicate with other modules. If scan tool communicates with other modules, go to next step. If scan tool does not communicate with other modules, perform PCI BUS COMMUNICATION FAILURE test.

NOTE: Steps 7 - 9 are written specifically for use with Chrysler's Diagnostic Readout Box (DRBIII(R)) scan tool.

Connect Scope Input Cable (CH7058) to channel one connector on scan tool. Connect Red and Black leads and Cable-To-Probe Adapter (CH7062) to scope input cable. Go to next step.
Using scan tool, select DRB STANDALONE, LAB SCOPE, LIVE DATA, then 12-VOLT SQUARE WAVE. Press F2 for scope. Press F2 again and use down arrow to set voltage range to 20 volts. Press F2 again. Go to next step.
Connect Black lead to chassis ground. Connect Red lead to PCM harness connectors, PCI bus circuit (Violet/Yellow wire). Turn ignition on. Observe voltage display on scan tool lab scope. If voltage pulses from zero to about 7.5 volts, replace PCM. See Figure -Figure . See POWERTRAIN CONTROL MODULE under REMOVAL & INSTALLATION. If voltage does not pulse from zero to about 7.5 volts, leave PCM connector disconnected and go to next step.
Turn ignition off. Disconnect BCM connector C3. Measure resistance of PCI bus circuit (Violet/Yellow wire) between BCM connector C3 terminal No. 7 and PCM C1 connector terminal No. 38. See Figure and Figure . If resistance is less than 5 ohms, replace BCM. See BODY CONTROL MODULE under REMOVAL & INSTALLATION. If resistance is 5 ohms or more, repair open in Violet/Yellow wire.