Diagnostic Aids

WARNING: This page is about a different variant/trim than selected.

Inspect all of the related wiring and connections including the connections at the TCM, as these may cause an intermittent concern. Inspect the terminals for any damage or any corrosion. Inspect the connector for any pushed-out terminals.

Diagnostic System Check - Automatic Transmission

Step	Action	Yes	No
1	Perform the following preliminary inspections: Ensure that the battery is fully charged. Refer to Battery Inspection/Test in Engine Electrical. Ensure that the battery cables are clean and tight. Inspect the easily accessible systems of the visible system components for obvious damage or conditions that could cause the symptom. Refer to Strategy Based Diagnosis in General Information. Ensure that the engine and control module grounds are clean, tight, and in the correct location. Inspect for aftermarket devices that could affect the operation of the system. Refer to Checking Aftermarket Accessories in Wiring Systems. Ensure the resistance between the TCM housing and the battery negative cable is less than 0.5 ohm. Did you find and correct the condition?	System OK	Go to Step 2
2	Turn ON the ignition, with the engine OFF. Attempt to establish communication with the listed control modules: Transmission control module (TCM) Engine control module (ECM) Electronic brake control module (EBCM) Instrument panel cluster (IPC) HVAC control module Theft deterrent control module Does the scan tool communicate with all the listed control modules?	Go to Step 3	Go to Scan Tool Does Not Communicate with Class 2 Device in Data Link Communications
3	IMPORTANT: The engine may start during the following step. Turn OFF the engine as soon as you have observed the Crank power mode. Access the Class 2 Power Mode in the Diagnostic Circuit Check on the scan tool. Rotate the ignition switch through all positions while observing the ignition switch power mode parameter. Refer to Body Control System Description and Operation in Body Control Systems for a list of the power mode states that correspond to each ignition switch position. Does the ignition switch parameter reading match the ignition switch position for all switch positions?	Go to Step 4	Go to Power Mode Mismatch in Body Control System
4	Attempt to start the engine. Does the engine crank?	Go to Step 5	Go to Symptoms - Engine Electrical in Engine Electrical
5	Did the engine start and idle?	Go to Step 6	Go to Engine Cranks but Does Not Run in Engine Controls - 2.6 and 3.2L or Engine Cranks but Does Not Run in Engine Controls - 3.6L
6	IMPORTANT: Do NOT clear the DTCs unless instructed by a diagnostic procedure. Select the DTC display function for the following control modules and record the DTCs: Transmission control module (TCM) Engine control module (ECM) Electronic brake control module (EBCM) Instrument panel cluster (IPC) HVAC control module Theft deterrent control module IF multiple powertrain DTCs are stored, diagnose the DTCs in the following order: Test for component lever DTCs. For example, sensor DTCs, then solenoid DTCs. Begin with the lowest number DTC unless the diagnostic table directs you otherwise. If there is any powertrain DTCs, Select Capture Info in order to store the Powertrain DTC information with a scan tool. Does the scan tool display any DTCs?	Go to Step 7	Go to Step 10
7	Does the scan tool display DTCs which begin with a "U"?	Go to Diagnostic Trouble Code (DTC) List in Data Link Communications	Go to Step 8
8	Does the scan tool display DTC P0601, P0602, P0603, P0604 or P1621?	Go to DTC P0601 , DTC P0602 , DTC P0603 , DTC P0604 or DTC P1621	Go to Step 9
9	Does the scan tool display DTC P0562 or P0563?	Go to DTC P0562 or DTC P0563	Go to Step 10
10	Are there any other TCM DTCs observed?	Go to Diagnostic Trouble Code (DTC) List/Type	Go to Step 11
11	Are there any ECM DTCs or driveability symptoms other than DTC P0700 observed?	Go to Diagnostic Trouble Code (DTC) List in Engine Controls - 2.6L and 3.2L or Diagnostic Trouble Code (DTC) List in Engine Controls - 3.6L	Go to Step 12
12	Are there any transmission controls or transmission driveability symptoms observed?	Go to Symptoms - Automatic Transmission	System OK