Important: Do not perform the Diagnostic System Check-Automatic Transmission unless one of the concerns noted is present. Failure to follow this procedure could lead to misdiagnosis of the system.
The Diagnostic System Check-Automatic Transmission is an organized approach to identifying a condition created by an electronic transmission control system. The Diagnostic System Check-Automatic Transmission is intended for use in diagnosing a concern in a vehicle with separate engine and transmission control modules, ECM and TCM.
When an emission related diagnostic trouble code (DTC) sets as a result of a transmission fault, the TCM requests the ECM to illuminate the malfunction indicator lamp (MIL). This request will be identified by the ECM as DTC P0700. The ECM may also independently illuminate the MIL. Although either module may cause the MIL to illuminate, the scan tool can display DTCs from only one module at a time. In addition, the Clear DTC Info command clears DTC data from both modules. If the DTC failure records are not recorded from both modules before the DTC data is cleared, important diagnostic information will be erased.
Your training and experience as a technician may cause you to focus on either the TCM or the ECM, instead of both modules at the same time. To ensure that both modules are properly diagnosed, separate system checks are included. The Diagnostic System Check - Engine Controls in Engine Controls - 2.2L identifies DTC status and communication function for the ECM. If no ECM DTCs are present, the Diagnostic System Check - Engine Controls in Engine Controls - 2.2L will direct you to the Diagnostic System Check-Automatic Transmission.
The ECM diagnostics do not require transmission data in order to run. Correct use of the tables will reduce diagnostic time and prevent the replacement of good parts.
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.
Step | Action | Yes | No | ||||||||||||
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1 | Perform the following preliminary inspections:
Did you find and correct the condition? | System OK | Go to Step 2 | ||||||||||||
2 |
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.
Does the ignition switch parameter reading match the ignition switch position for all switch positions? | Go to Step 4 | Go to Control Module References 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 - 2.2L | ||||||||||||
6 |
Important: Do NOT clear the DTCs unless instructed by a diagnostic procedure.
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. 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 P0606? | Go to DTC P0601 , DTC P0602 , DTC P0603 , DTC P0604 or DTC P0606 | Go to Step 9 | ||||||||||||
9 | Does the scan tool display DTC P0562 or P0563? | Go to Step 10 | |||||||||||||
10 | Are there any other TCM DTCs observed? | Go to Step 11 | |||||||||||||
11 | Are there any ECM DTCs or drivability symptoms other than DTC P0700 observed? | Go to Diagnostic Trouble Code (DTC) List in Engine Controls-2.2L | Go to Step 12 | ||||||||||||
12 | Are there any transmission controls or transmission drivability symptoms observed? | System OK |