For 1990-2009 cars

### Circuit Description

The flow of transmission fluid starts in the bottom pan and is drawn through the filter, control valve body assembly, transmission case and into the oil pump assembly. The oil pump assembly pressurizes the fluid and directs it to the pressure regulator valve where it becomes the main supply of fluid to the various components and hydraulic circuits in the transmission. Hot fluid exiting the torque converter flows through the converter clutch apply valve and into the transmission cooler lines to the oil cooler located in the vehicle radiator, and auxiliary cooler if equipped. From the cooler, fluid returns to cool and lubricate the front of the transmission. In forward drive ranges, D4 fluid from the manual valve is routed through an orificed cup plug in the rear of the transmission case to feed the rear lube fluid circuit.

When the powertrain control module (PCM) detects a high transmission fluid temperature (TFT) for a long period of time, then DTC P0218 sets. DTC P0218 is a type C DTC.

### DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC P0218 Transmission Condition Overtemperature

### Conditions for Running the DTC

• | No TFT sensor DTCs P0711, P0712 or P0713.

• | The ignition switch is ON for 5 seconds.

• | Engine RPM greater than 475 for 5 seconds.

### Conditions for Setting the DTC

The TFT is greater than 130°C (266°F) for 600 seconds (10 minutes).

### Action Taken When the DTC Sets

• | The PCM does not illuminate the malfunction indicator lamp (MIL).

• | Check Trans Fluid and Trans Hot....IDLE ENGINE messages are displayed on the driver information center (DIC).

• | The PCM freezes transmission adapt functions.

• | The PCM records the operating conditions when the Conditions for Setting the DTC are met. The PCM stores this information as Failure Records.

• | The PCM stores DTC P0218 in PCM history.

### Conditions for Clearing the DTC

• | A scan tool can clear the DTC.

• | The PCM clears the DTC from PCM history if the vehicle completes 40 warm-up cycles without a non-emission related diagnostic fault occurring.

• | The PCM cancels the DTC default actions when the fault no longer exists and the DTC passes.

### Diagnostic Aids

• | The scan tool Trans. Fluid Temp. should rise steadily to a normal operating temperature, then stabilize.

• | Ask about the customer's driving habits, trailer towing, etc. Trailer towing should occur in D3.

• | Refer to Symptoms - Automatic Transmission .

### Test Description

The numbers below refer to the step numbers on the diagnostic table.

1. This step inspects for air flow restrictions or damage which may result from the transmission overheating.

#### DTC P0218

Step | Action | Values | Yes | No
--- | --- | --- | --- | ---
1 | Did you perform the Diagnostic System Check - Vehicle? | -- | Go to Step 2 | Go to Diagnostic System Check - Vehicle
2 |

1. Install a scan tool.
2. Turn ON the ignition, with the engine OFF.

Important: Before clearing the DTC, use the scan tool in order to record the Failure Records. Using the Clear Info function erases the Failure Records from the powertrain control module (PCM).

3. Record the DTC Failure Records.
4. Clear the DTC.
5. Inspect for correct transmission fluid level. Refer to Transmission Fluid Check .

Did you perform the fluid checking procedure?

--

Go to Step 3

Go to Transmission Fluid Check

3 |

1. Inspect the engine cooling system and transmission cooling system for the following conditions:

• | Air flow restrictions

• | Air flow blockage

• | Debris

2. Inspect the transmission cooling system for damaged cooler lines.
3. Test the oil cooler flow.

Refer to Transmission Fluid Cooler Flushing and Flow Test .

Did you find and correct the condition?

--

Go to Step 6

Go to Step 4

4 | Test for correct line pressure. Refer to Line Pressure Check . Did you find and correct the condition? | -- | Go to Step 6 | Go to Step 5
5 | Test the torque converter stator. Refer to Torque Converter Diagnosis . Did you find and correct the condition? | -- | Go to Step 6 | Go to Testing for Intermittent Conditions and Poor Connections
6 | Perform the following procedure in order to verify the repair:

1. Install a scan tool.
2. Select DTC.
3. Select Clear Info.
4. Start and idle the engine until it reaches normal operating temperature.
5. Monitor Engine Run Time and Trans. Fluid Temp. on the scan tool.
6. Drive the vehicle for 10 minutes.
7. Ensure that the transmission fluid temperature has stabilized and is less than 129°C (264°F).
8. Select Specific DTC.
9. Enter DTC P0218.

Has the test run and passed?

--

Go to Step 7

Go to Step 2

7 | With the scan tool, observe the stored information, capture info, and DTC Info. Does the scan tool display any DTCs that you have not diagnosed? | -- | Go to Diagnostic Trouble Code (DTC) List - Vehicle | System OK