DTC 55. Chevrolet Joy 2008

For 1990-2009 cars

### Circuit Description

Selector switch (park/neutral switch) wrong signal.

### Conditions for Running the DTC

• | Road test the vehicle. Refer to Road Test .

• | Moving selector lever through all ranges.

### Conditions for Setting the DTC

• | Selector lever position switch coding logic does not indicate a valid combination.

• | Condition must be fulfilled for at least 5 seconds.

### Action Taken When the DTC Sets

• | The transmission control module (TCM) illuminates the A/T warning lamp when the diagnostic runs and fails.

• | Shifting is manual (Emergency Program).

### Conditions for Clearing the MIL/DTC

The TCM turns OFF the A/T warning lamp when the diagnostic runs and does not fail.

### Test Description

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

1. Test the range circuits.

2. Test the range circuits.

3. Test the range circuits.

4. Test the range circuits.

5. Test the range circuits.

6. Test the range circuits.

7. Tests for voltage on an incorrect range circuit.

8. Tests the ignition voltage feed circuit.

9. Tests for voltage on an incorrect range circuit.

10. Checks adjustment of the component.

11. Verifies That DTC 55 has been received.

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

2

1. Apply the parking brake.
2. Turn OFF the ignition.
3. Disconnect transmission control module (TCM) connector.
4. Leave selector in PARK.
5. Turn ON the ignition with the engine OFF.
6. Connect a test lamp to each of the range circuits at the TCM connector.

Does the test light illuminate for only the P range circuit?

Go to Step 3

Go to Step 8

3

1. Turn OFF the ignition.
2. Place the selector in REVERSE.
3. Turn ON the ignition with the engine OFF.
4. Connect a test lamp to each of the range circuits at the TCM connector.

Does the test light illuminate for only the R range circuit?

Go to Step 4

Go to Step 10

4

1. Turn OFF the ignition.
2. Place the selector in NEUTRAL.
3. Turn ON the ignition with the engine OFF.
4. Connect a test lamp to each of the range circuits at the TCM connector.

Does the test light illuminate for only the N range circuit?

Go to Step 5

Go to Step 10

5

1. Turn OFF the ignition.
2. Place the selector in DRIVE.
3. Turn ON the ignition with the engine OFF.
4. Connect a test lamp to each of the range circuits at the TCM connector.

Does the test light illuminate for only the D range circuit?

Go to Step 6

Go to Step 10

6

1. Turn OFF the ignition.
2. Place the selector in SECOND.
3. Turn ON the ignition with the engine OFF.
4. Connect a test lamp to each of the range circuits at the TCM connector.

Does the test light illuminate for only the 2 range circuit?

Go to Step 7

Go to Step 10

7

1. Turn OFF the ignition.
2. Place the selector in LOW.
3. Turn ON the ignition with the engine OFF.
4. Connect a test lamp to each of the range circuits at the TCM connector.

Does the test light illuminate for only the L range circuit?

Go to Step 12

Go to Step 10

8 | Did the test light illuminate for more than one range circuit? | Go to Step 11 | Go to Step 9

9

1. Disconnect the select switch.
2. Test the ignition circuit at the select switch for an ope or short to ground. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 16

Go to Step 12

10 | Did the test light illuminate for more than one range circuit? | Go to Step 11 | Go to Step 12
11 | Test for a short to voltage in the incorrect range circuit. Refer to Testing for a Short to Voltage and Wiring Repairs . Did you find and correct the condition? | Go to Step 16 | Go to Step 14
12 | Test the range circuit for an open or short to ground. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition? | Go to Step 16 | Go to Step 13
13 | Check adjustment of the select switch. Did you find and correct the condition? | Go to Step 16 | Go to Step 14
14 | Replace the select switch. Refer to Park/Neutral Position Switch Replacement . Did you find and correct the condition? | Go to Step 16 | --
15 | Replace the TCM. Refer to Transmission Control Module Replacement . Did you complete the replacement? | Go to Step 16 | --

16

1. Clear the DTCs. Refer to Clearing Transmission Diagnostic Trouble Codes .
2. Turn the ignition OFF for 30 seconds.
3. Start the engine.
4. Operate the vehicle within Conditions for Running the DTC.

Does the DTC reset?

Go to Step 2

System OK