• | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
• | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
• | Diagnostic Procedure Instructions provides an overview of each diagnostic category. |
Transmission fluid is drawn from the bottom pan through the filter, case assembly, channel plate assembly, control valve body assembly, and into the oil pump assembly. The pump is mounted on the control valve body assembly. Fluid pressure leaving the pump is controlled by the pressure regulator valve and becomes the main supply of line pressure to the various components and hydraulic circuits. Hot fluid from the torque converter flows through the torque converter clutch (TCC) control valve into the cooler lines to the oil cooler located in the vehicle radiator and auxiliary cooler, if equipped. Cool fluid then returns to lubricate the final drive assembly and other components along the output shaft.
• | The ignition voltage is between 8 and 18 volts. |
• | The transmission fluid temperature (TFT) is between -39 to +149°C (-38 to +300°F) for 5 seconds. |
The TFT is greater than 140°C (286°F) for 1 minute.
DTC P0218 is a Type C DTC.
DTC P0218 is a Type C DTC.
Automatic Transmission Controls Schematics
Transmission General Description
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
• | J 35616 GM-Approved Terminal Test Kit |
• | J 44152 Jumper Harness (20 pins) |
Ensure that the transmission fluid level is at the proper level by performing the Transmission Fluid Check .
⇒ | If the level is not within specifications, repair as necessary. |
• | Transmission line pressure low. Refer to Line Pressure Check . |
• | Transmission fluid flow through cooler and/or auxiliary cooler, if equipped, is restricted due to the following conditions: |
- | Transmission fluid level low |
- | A clogged filter |
- | A leaking filter or seal |
- | Plugged, kinked, or damaged transmission cooler pipes |
- | Refer to Transmission Fluid Cooler Flushing and Flow Test . |
• | Air flow through transmission fluid cooler and/or auxiliary cooler, if equipped, is restricted due to the following conditions: |
- | Damaged fins |
- | Debris |
• | Engine overheating due to the following conditions: |
- | Low coolant level |
- | Inspect coolant temperature, coolant level, and hoses |
- | Restricted air flow |
- | Restricted coolant flow |
- | Refer to Engine Overheating . |
Perform the Diagnostic Repair Verification after completing the repair.
• | Control Module References for TCM replacement, setup, and programming. |