Test Description
WARNING: This page is about a different variant/trim than selected.
The numbers below refer to the step numbers on the diagnostic table.
- 1: This step determines if the scan tool is receiving power through the DLC connector.
- 2: The MIL should illuminate whenever the ignition is ON and the engine is not running.
- 3: This step determines if the PCM is transmitting class 2 serial data to the DLC and that the class 2 data circuit is not open or shorted.
- 4: This step determines if a DTC is current or stored in history.
Diagnostic System Check - Automatic Transmission
| Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
| 1 |
IMPORTANT:
Check for applicable service bulletins before proceeding with this test. Perform this test only if there is a driveability complaint or if you have been directed to this table from another section in the service information.
IMPORTANT:
Do not turn the ignition OFF when performing this diagnostic procedure. Do not clear the DTCs unless instructed by this diagnostic procedure.
|
- | Go to Step 2 | Go to Diagnostic Starting Point - Data Link Communications in Data Link Communications |
| 2 | Is the MIL ON? | - | Go to Step 3 | Go to Malfunction Indicator Lamp (MIL) Inoperative in Engine Controls - 4.8L, 5.3L and 6.0L |
| 3 | Attempt to establish communication with the PCM. Does the scan tool communicate with the PCM? |
- | Go to Step 4 | Go to Diagnostic Starting Point - Data Link Communications in Data Link Communications |
| 4 |
IMPORTANT:
Diagnostic Trouble Codes (DTCs), engine performance, and transmission default actions can greatly affect the transmission performance. Ensure that these items are not the cause of a transmission concern. Use the scan tool Capture Info function in order to save or capture (Store Info) any DTC Information.Are there any DTCs present? |
- | Go to Diagnostic Trouble Code (DTC) List/Type | Go to Symptoms - Automatic Transmission |